A new photocopier can make 72 copies in 2 min. When an older photocopier is working, the two photocopiers can make 72 copies in 1.5 min. How long will it take the older photocopier working alone to make 70 copies?
To determine how long it will take the older photocopier working alone to make 70 copies, we can set up a proportion based on the information given.
Let's say the rate of the new photocopier is "x" copies per minute.
The rate of the older photocopier then becomes (72 - x) copies per minute, as the combined rate of the two copiers is 72 copies in 1.5 minutes.
Using the formula: Rate × Time = Amount, we can set up the following equations:
Rate of new copier × 2 minutes = 72 copies
Rate of new copier = 72 copies / 2 minutes = 36 copies per minute
Rate of older copier × 1.5 minutes = 72 copies
Rate of older copier = 72 copies / 1.5 minutes = 48 copies per minute
Now, we can set up a proportion to find the time it takes for the older copier to make 70 copies, let's call it "t".
48 copies per minute × t minutes = 70 copies
48t = 70
t = 70 / 48
t ≈ 1.46 minutes
Therefore, it would take the older photocopier working alone approximately 1.46 minutes to make 70 copies.