Question

A plumber had two pipes. The ratio of the length of the longer pipe to the shorter pipe was 9:2. When he cut 1.65m from the longer pipe, the remaining length was 3 times that of the shorter pipe. Find the length of the shorter pipe in metres.

Answer 1

Answer:

1.1m

Step-by-step explanation:

Let L denote longer pipe and S denote shorter part

given:

L:S = 9:2

or L/S = 9/2

2L = 9S

S = (2/9)L-----(eq 1)

Also given:

L - 1.65 = 3S

L - 3S = 1.65 ----- (eq 2)

By substitution, sub eq 1 into eq 2

L - 3(2/9)L = 1.65

L - (2/3)L = 1.65

L [ 1 - (2/3) ] = 1.65

L/3 = 1.65

L = 1.65 (3) = 4.95  (substitute into equation 1)

S = (2/9)(4.95) = 1.1m