Sara can lift a 10-pound weight by applying 30 pounds of force to a lever. If the amount of force Sara needs to apply to a lever is proportional to the weight she can lift, how much force would she need to apply in order to lift a 25-pound weight?

Jun 30, 2018

$75$ pounds of force to the lever.

Explanation:

We know that the force she applies to the lever is directly proportional to the weight she can lift.

So, we get:

$\frac{30}{10} = \frac{{F}_{{l}_{2}}}{25}$

$3 = \frac{{F}_{{l}_{2}}}{25}$

$\therefore {F}_{{l}_{2}} = 3 \cdot 25$

$= 75$