Question
Quantitative Aptitude Question on Logarithms
If log 2(5+log3a)=3 and log5(4a+12+log2b) = 3, then a+b is equal to
A
67
B
40
C
32
D
59
Answer
59
Explanation
Solution
The correct answer is (D):
5+log3a = 23 = 8 ⇒ a = 27
Similarly, 4a+12+log2b = 53 = 125
since a = 27, 4(27)+12+log2b = 125 ⇒ b = 32
a + b = 59.