Question

3 roads, A, B, and C. B is three times longer than A. C is twice as long as B. What fraction of the total length of the roads is the length of A? If Road B is 7 miles longer than Road A, what is the length of Road C?

Answer 1

0.1 and 21

Explanation:

Here B = 3A & C = 2B = 2 x 3A = 6A.

Again, B = 7 + A
Hence, 3A = 7 + A. So, A = 7/2.

Now lengths of the road = A + B + C = A + 3A + 6A = 10A = 10 x 7/2 = 35 miles.

Let x fraction of 35 = A =7/2.
Or, x = `7/2. 1/35 = 1/10 = 0.1`

Length of road C = 6A = 6 x 7/2 = 21 miles.

Therefore, 0.1 fraction of the total lengths of the road is the length of A and length of road C is 21 miles.