Answer:
12 minutes.
Step-by-step explanation:
Marla uses two copiers to make copies of a one-page newsletter. *Copier R makes 60 copies per minute. *Copier T makes 40 copies per minute.
Since both copier start at the same time, let the number of minutes used by both copiers be represented by x
60 × x + 40 × x = 1200 copies
60x + 40x = 1200
100x = 1200
x = 1200/100
x = 12 minutes
Therefore, it will take 12 minutes l to make 1200 copies.