Question:
Mark (✓) against the correct answer
If 6x5 is exactly divisible by 9, then the least value of x is
(a) 1
(b) 4
(c) 7
(d) 0
Solution:
(c) 7
When a number is divisible by 9, the sum of the digits is also divisible by 9.
$6+x+5=11+x$
To be divisible by 9 :
$11+x=18 \Rightarrow x=7$