{"id":92379,"date":"2025-06-01T11:22:32","date_gmt":"2025-06-01T11:22:32","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=92379"},"modified":"2025-06-01T11:22:32","modified_gmt":"2025-06-01T11:22:32","slug":"what-is-the-number-of-all-possible-positive-integer-values-of-n-for","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/","title":{"rendered":"What is the number of all possible positive integer values of &#8216;n&#8217; for"},"content":{"rendered":"<p>What is the number of all possible positive integer values of &#8216;n&#8217; for which n\u00b2 + 96 is a perfect square ?<\/p>\n<p>[amp_mcq option1=&#8221;2&#8243; option2=&#8221;4&#8243; option3=&#8221;5&#8243; option4=&#8221;Infinite&#8221; correct=&#8221;option2&#8243;]<\/p>\n<div class=\"psc-box-pyq-exam-year-detail\">\n<div class=\"pyq-exam\">\n<div class=\"psc-heading\">This question was previously asked in<\/div>\n<div class=\"psc-title line-ellipsis\">UPSC CISF-AC-EXE &#8211; 2017<\/div>\n<\/div>\n<div class=\"pyq-exam-psc-buttons\"><a href=\"\/pyq\/pyq-upsc-cisf-ac-exe-2017.pdf\" target=\"_blank\" class=\"psc-pdf-button\" rel=\"noopener\">Download PDF<\/a><a href=\"\/pyq-upsc-cisf-ac-exe-2017\" target=\"_blank\" class=\"psc-attempt-button\" rel=\"noopener\">Attempt Online<\/a><\/div>\n<\/div>\n<section id=\"pyq-correct-answer\">\nThe correct answer is B.<br \/>\n<\/section>\n<section id=\"pyq-key-points\">\nWe are looking for positive integer values of &#8216;n&#8217; such that n\u00b2 + 96 is a perfect square.<br \/>\nLet n\u00b2 + 96 = k\u00b2, where k is an integer.<br \/>\nSince n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k > n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96).<br \/>\nRearranging the equation, we get k\u00b2 &#8211; n\u00b2 = 96.<br \/>\nThis is a difference of squares, which can be factored as (k &#8211; n)(k + n) = 96.<br \/>\nSince k and n are integers, (k-n) and (k+n) must be integer factors of 96.<br \/>\nAlso, (k+n) &#8211; (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even.<br \/>\nFurthermore, since n is positive, k+n > k-n. Also, k+n > 0 (as n>0 and k>n).<br \/>\n<\/section>\n<section id=\"pyq-additional-information\">\nWe need to find pairs of even factors (a, b) of 96 such that a * b = 96 and b > a.<br \/>\nThe factors of 96 are 1, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 96.<br \/>\nThe even factors are 2, 4, 6, 8, 12, 16, 24, 32, 48, 96.<br \/>\nPairs (a, b) where a and b are even, a*b=96, and b > a:<br \/>\n1. (2, 48) -> k &#8211; n = 2, k + n = 48. Adding gives 2k=50, k=25. Subtracting gives 2n=46, n=23. (n=23 is a positive integer)<br \/>\n2. (4, 24) -> k &#8211; n = 4, k + n = 24. Adding gives 2k=28, k=14. Subtracting gives 2n=20, n=10. (n=10 is a positive integer)<br \/>\n3. (6, 16) -> k &#8211; n = 6, k + n = 16. Adding gives 2k=22, k=11. Subtracting gives 2n=10, n=5. (n=5 is a positive integer)<br \/>\n4. (8, 12) -> k &#8211; n = 8, k + n = 12. Adding gives 2k=20, k=10. Subtracting gives 2n=4, n=2. (n=2 is a positive integer)<br \/>\nWe found 4 distinct positive integer values for n: 23, 10, 5, and 2.<br \/>\nTherefore, there are 4 possible positive integer values of &#8216;n&#8217; for which n\u00b2 + 96 is a perfect square.<br \/>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>What is the number of all possible positive integer values of &#8216;n&#8217; for which n\u00b2 + 96 is a perfect square ? [amp_mcq option1=&#8221;2&#8243; option2=&#8221;4&#8243; option3=&#8221;5&#8243; option4=&#8221;Infinite&#8221; correct=&#8221;option2&#8243;] This question was previously asked in UPSC CISF-AC-EXE &#8211; 2017 Download PDFAttempt Online The correct answer is B. We are looking for positive integer values of &#8216;n&#8217; &#8230; <\/p>\n<p class=\"read-more-container\"><a title=\"What is the number of all possible positive integer values of &#8216;n&#8217; for\" class=\"read-more button\" href=\"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/#more-92379\">Detailed Solution<span class=\"screen-reader-text\">What is the number of all possible positive integer values of &#8216;n&#8217; for<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1089],"tags":[1101,1102],"class_list":["post-92379","post","type-post","status-publish","format-standard","hentry","category-upsc-cisf-ac-exe","tag-1101","tag-quantitative-aptitude-and-reasoning","no-featured-image-padding"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v22.2 (Yoast SEO v23.3) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>What is the number of all possible positive integer values of &#039;n&#039; for<\/title>\n<meta name=\"description\" content=\"The correct answer is B. We are looking for positive integer values of &#039;n&#039; such that n\u00b2 + 96 is a perfect square. Let n\u00b2 + 96 = k\u00b2, where k is an integer. Since n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k &gt; n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96). Rearranging the equation, we get k\u00b2 - n\u00b2 = 96. This is a difference of squares, which can be factored as (k - n)(k + n) = 96. Since k and n are integers, (k-n) and (k+n) must be integer factors of 96. Also, (k+n) - (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even. Furthermore, since n is positive, k+n &gt; k-n. Also, k+n &gt; 0 (as n&gt;0 and k&gt;n).\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"What is the number of all possible positive integer values of &#039;n&#039; for\" \/>\n<meta property=\"og:description\" content=\"The correct answer is B. We are looking for positive integer values of &#039;n&#039; such that n\u00b2 + 96 is a perfect square. Let n\u00b2 + 96 = k\u00b2, where k is an integer. Since n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k &gt; n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96). Rearranging the equation, we get k\u00b2 - n\u00b2 = 96. This is a difference of squares, which can be factored as (k - n)(k + n) = 96. Since k and n are integers, (k-n) and (k+n) must be integer factors of 96. Also, (k+n) - (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even. Furthermore, since n is positive, k+n &gt; k-n. Also, k+n &gt; 0 (as n&gt;0 and k&gt;n).\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T11:22:32+00:00\" \/>\n<meta name=\"author\" content=\"rawan239\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"rawan239\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"What is the number of all possible positive integer values of 'n' for","description":"The correct answer is B. We are looking for positive integer values of 'n' such that n\u00b2 + 96 is a perfect square. Let n\u00b2 + 96 = k\u00b2, where k is an integer. Since n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k > n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96). Rearranging the equation, we get k\u00b2 - n\u00b2 = 96. This is a difference of squares, which can be factored as (k - n)(k + n) = 96. Since k and n are integers, (k-n) and (k+n) must be integer factors of 96. Also, (k+n) - (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even. Furthermore, since n is positive, k+n > k-n. Also, k+n > 0 (as n>0 and k>n).","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/","og_locale":"en_US","og_type":"article","og_title":"What is the number of all possible positive integer values of 'n' for","og_description":"The correct answer is B. We are looking for positive integer values of 'n' such that n\u00b2 + 96 is a perfect square. Let n\u00b2 + 96 = k\u00b2, where k is an integer. Since n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k > n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96). Rearranging the equation, we get k\u00b2 - n\u00b2 = 96. This is a difference of squares, which can be factored as (k - n)(k + n) = 96. Since k and n are integers, (k-n) and (k+n) must be integer factors of 96. Also, (k+n) - (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even. Furthermore, since n is positive, k+n > k-n. Also, k+n > 0 (as n>0 and k>n).","og_url":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T11:22:32+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/","url":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/","name":"What is the number of all possible positive integer values of 'n' for","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T11:22:32+00:00","dateModified":"2025-06-01T11:22:32+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"The correct answer is B. We are looking for positive integer values of 'n' such that n\u00b2 + 96 is a perfect square. Let n\u00b2 + 96 = k\u00b2, where k is an integer. Since n is a positive integer, n\u00b2 is positive, so k\u00b2 must be greater than n\u00b2. This implies k > n (assuming k is positive, which it must be since k\u00b2 = n\u00b2 + 96). Rearranging the equation, we get k\u00b2 - n\u00b2 = 96. This is a difference of squares, which can be factored as (k - n)(k + n) = 96. Since k and n are integers, (k-n) and (k+n) must be integer factors of 96. Also, (k+n) - (k-n) = 2n. Since n is an integer, 2n is an even integer. This means (k-n) and (k+n) must have the same parity. Since their product (96) is even, both factors must be even. Furthermore, since n is positive, k+n > k-n. Also, k+n > 0 (as n>0 and k>n).","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/what-is-the-number-of-all-possible-positive-integer-values-of-n-for\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/exam.pscnotes.com\/mcq\/"},{"@type":"ListItem","position":2,"name":"UPSC CISF-AC-EXE","item":"https:\/\/exam.pscnotes.com\/mcq\/category\/upsc-cisf-ac-exe\/"},{"@type":"ListItem","position":3,"name":"What is the number of all possible positive integer values of &#8216;n&#8217; for"}]},{"@type":"WebSite","@id":"https:\/\/exam.pscnotes.com\/mcq\/#website","url":"https:\/\/exam.pscnotes.com\/mcq\/","name":"MCQ and Quiz for Exams","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/exam.pscnotes.com\/mcq\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209","name":"rawan239","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","caption":"rawan239"},"sameAs":["https:\/\/exam.pscnotes.com"],"url":"https:\/\/exam.pscnotes.com\/mcq\/author\/rawan239\/"}]}},"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/92379","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/comments?post=92379"}],"version-history":[{"count":0,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/92379\/revisions"}],"wp:attachment":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/media?parent=92379"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/categories?post=92379"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/tags?post=92379"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}