A, B and C together can complete a work in x, 30 and 45 days, respectively. B and C worked together for 6 days. The remaining work was completed by A alone in 12 days. The value of x is:
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 18.
Let's assume A can finish the work = x days
So, the total work = LCM of A, B, and C = 90x
So,
The efficiency of A = 90
B = 90x/30 = 3x
C = 90x/45 = 2x
According to the question,
B and C works for 6 days = (3x + 2x)6 = 30x
Remaining work finsh by A = 12 days
(90x - 30x)/90 = 12
x = 18