Question
Quantitative Aptitude Question on Surface Area of Cube, Cuboid and Cylinder
If 25(3a-2b) = 5(b-a) = 52 and , then find the value of ab - c.
A
1
B
0
C
-1
D
-2
Answer
0
Explanation
Solution
The correct option is (B): 0.
25(3a-2b) = 5(b-a) = 52
52 (3a-2b) = 5(b-a) = 52
5(6a-4b) = 5(b-a) = 52
5(6a-4b) = 52
6a - 4b = 2
3a - 2b = 1 .............. (1)
5(b-a) = 52
b - a = 2
2b - 2a = 4 .............. (2)
From (1) and (2):
3a - 2a - 4 = 1
a = 5
b = 7
Now,
c= 35
value of ab - c
= 5 * 7 - 35
= 35 - 35
= 0