X paid ₹ 47 for certain cups of tea and coffee. If tea costs ₹ 5 per cup and coffee costs ₹ 8 per cup, which one of the following statements is correct ?
[amp_mcq option1=”He drank 8 cups of tea and coffee.” option2=”He drank the same number of cups of tea and coffee.” option3=”He drank more tea than coffee.” option4=”He drank more coffee than tea.” correct=”option4″]
This question was previously asked in
UPSC CISF-AC-EXE – 2017
We can try possible values for c:
If c=0, 5t = 47 (not possible for integer t)
If c=1, 5t = 47 – 8 = 39 (not possible for integer t)
If c=2, 5t = 47 – 16 = 31 (not possible for integer t)
If c=3, 5t = 47 – 24 = 23 (not possible for integer t)
If c=4, 5t = 47 – 32 = 15 => t = 3. This is a valid integer solution (t=3, c=4).
If c=5, 5t = 47 – 40 = 7 (not possible for integer t)
If c=6, 5t = 47 – 48 = -1 (not possible for non-negative t)
The only valid solution is t=3 cups of tea and c=4 cups of coffee.
Based on this solution:
A) Total cups = 3 + 4 = 7, not 8. (Incorrect)
B) Number of tea cups (3) is not the same as coffee cups (4). (Incorrect)
C) He drank 3 cups of tea and 4 cups of coffee. 3 is not more than 4. (Incorrect)
D) He drank 4 cups of coffee and 3 cups of tea. 4 is more than 3. (Correct)