CMAT 2022 Question 19
This is a detailed step-by-step solution for CMAT 2022 Question 19. Understand the concept, common mistakes, and expert tips to solve similar questions in CMAT exam.
CMAT 2022
Statement I:
Given arithmetic mean of (7,8,9,a,b,10,8,7) is 9 and mode is 8
7+8+9+a+b+10+8+7 =
49+a+b = 72
a+b = 23
It is mentioned that mode is 8, 8 occurred twice and 7 also occurred twice. Therefore, a or b should be 8
If a = 8, b = 15
If b = 8, a = 15
ab = 120
Statement I is true
Statement II:
a + b + ab = 84
1 + a + b + ab = 85
(1+a)(1+b) = 85
85 = 1 85 or 5 17
It cannot be 1 85, as it is mentioned both a and b are positive integers
If 1+a = 5, 1+b = 17
a =4 and b = 16
If 1+a = 17, 1+b = 5
a = 16 and b = 4
In both cases, a+b = 20
Statement II is true
Answer is option A.