498,225 views
26 votes
26 votes
In 2 minutes, a conveyor belt moves 800 pounds of recyclable aluminum from the delivery truck to a storage area. A smaller belt moves the same quantity of cans the same distance in 3 minutes. If both belts are used, find how long it takes to move the cans to the storage area.

User Max Vasileuski
by
2.9k points

1 Answer

27 votes
27 votes

It will take 1.2 minutes if the two belts are used together

Here, we will be working with calculating joint rate

The rate for the bigger belt is;


\frac{800\text{ lbs}}{2\text{ minutes }}\text{ = 400 lbs/min}

For the smaller belt, the rate is;


\frac{800\text{ lbs}}{3\text{ minutes }}\text{ = }(800)/(3)\text{ lbs/min}

Now, since we are combining both belts, we will be combining their rates

So, we simply divide the total weight by the addition of the rates

Thus, we have this as;


\begin{gathered} (800)/(400+(800)/(3)) \\ =\text{ }(800)/((1200+800)/(3)) \\ \\ =\text{ }(800)/((2000)/(3)) \\ =\text{ 800 }*\text{ }(3)/(2000)\text{ = }(2400)/(2000)\text{ = 1.2 minutes} \end{gathered}

User Fionna
by
2.6k points