What is the answer?

If A and B can do a work in 30 days, B and C can do the same work in 24 days and C and A in 20 days. In how many days the work will be completed , if they all work together?

I got 16. What do you guys think??

Here's the working:

2*(A+B+C)= 1/30+1/24+1/20= 1/8 So, A+B+C s work in 1 hour can accomplish 1/16th of the project. To complete the entire project ( 16/16) , multiply 16 with 1 hour = 16 hours. No? I got marked wrong.

Easy Math Editor

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Comments

16 is the right answer.

sand eee - 7 years, 3 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$