How far will the spring stretch if the weight is increased?

Question

The length that a hanging spring stretches varies directly as the weight placed at the end of the spring. If a weight of 17⁢lb stretches a certain spring 7in, how far will the spring stretch if the weight is increased to 43⁢lb? Round your answer to the nearest integer if necessary.

Answer 1

Let the weight of the spring be w.

Let the length stretched be l.

Since it is a directvariation, w= k( l )

where k, is the constant of proportionality.

Substituting, 17 = k(7).

Determine k.

Now use this k and set up the equation 43 = k (L)

and determine L.

L is the length the spring stretches to when the weight is 43 lb.