Respuesta :

Dasaherals
6 minutes because 28/8 is 3.5 that is the number of photos that the printer prints in one minute so you / 21 into 3.5 and that is 6 minutes
kase12
First you have to divide 28 by 8 to find the amount per 1 minute.
Which equals 3.5 photos per minutes.

Then you have to divide 21 by the photos per minute.

Which gives you your answer; It takes 6 minutes to print 21 more photos