Answer:
It takes 2 minutes 4 seconds to move the cans to storage area if both the belts are used.
Step-by-step explanation:
Given - In 4 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 6 minutes.
To find - If both belts are used, find how long it takes to move the cans
to the storage area.
Proof -
Given that,
Larger belt take 4 minutes to transfer the aluminium from delivery truck to storage area.
⇒ Time taken by Larger belt = 4 min/ shifting
Also,
Smaller belt take 6 minutes to transfer the aluminium from delivery truck to storage area.
⇒ Time taken by Smaller belt = 6 min/ shifting
Now,
As we know that Time is inversely proportional to time, so
Rate of Larger Belt = 
shifting/min
Rate of Smaller Belt = 
shifting/min
Now,
Let us assume that , if both belts used then,
Total time taken = x min/shifting
Then, Rate = 
shifting/min
Now,
+ =
⇒
⇒
⇒10x = 24
⇒x = 
= 2.4 minutes
∴ we get
It takes 2 minutes 4 seconds to move the cans to storage area if both the belts are used.
