When 12, 16, 18, 20 and 25 divide the least number x, the remainder in each case is 4 but x is divisible by 7. What is the digit at the thousand’s place in x?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is 2 ie 8.
n = k{ LCM (12, 16, 18, 20, 25)} + 4
n = (k × 144 × 25) + 4
n = 3600k + 4
n = 3598k + 2k +4
(2k + 5) / 7, k = 5
n = 18004
Digit at thousand’s place = 8