SOLUTION: A weight of 250g stretches a spring to a distance of 9.5 cm. If the distance stretched is directly proportional to the attached weight, what weight will stretch the spring to 5.7cm

The vertical spring formula is



where  = the weight placed on the spring,
       = the spring constant
       = the distance in cm the spring stretches when
a weight of  grams is placed on it.

We don't know the spring constant.  We find it from

>>...A weight of 250g stretches a spring to a distance of 9.5 cm...<<

So we substitute  and  into :



Divide both sides by 9.5



Now we substitute  into the spring formula:





Now our formula is complete and we can now solve the problem
asked for:

>>...what weight will stretch the spring to 5.7cm?...<<

Substitute  into the complete formula 





Edwin