What is the answer of this question.

Question

A 120 foot rope is cut into 3 pieces.The first piece of the rope is twice as long as the second piece of rope.The third piece of rope is three time as long as the second piece of rope.What is the longest piece of rope.
a 20 feet
b 40 feet
c 60 feet
d 80 feet

Answer 1

You don't need to do much work. Your longest piece is 3 times the shortest, so your answer has to be a multiple of 3. To test that, add the digits. If that's divisible by 3, the number is divisible by 3.

 

For example, A, 20.

 

2 + 0 = 2 and 2 is not divisible by 3, so 20 is not divisible by 3.