Question

the local hardware store wants to increase their inventory. Last year 15 electric screwdrivers cost them 300.how much would 45 screwdrivers cost

Answer 1

One way of doing this is to write the equation of ratios (15 screwdrivers / 45 screwdrivers) = ($300 / x).    Solve this equation for x.  To do this, you might try multiplying both sides of this equation by x to eliminate fractions.

Another way is to obtain the unit cost of each screwdriver and then multiply the result by 45 screwdrivers.