The time T necessary to make an enlargement of a photo negative varies directly as the area A of the enlargement. If 90 seconds are required to make a 3-by-5 enlargement, find the time required
For a 5-by-6 enlargement.
A)210 sec
B)150 sec
C)240 sec
D)180 sec

Question

Quizplus · Accepted Answer

The area of the 3-by-5 enlargement is 15 square units, and it takes 90 seconds. The area of the 5-by-6 enlargement is 30 square units. Since time varies directly with area, the time required is (90/15) * 30 = 180 seconds.

The Time T Necessary to Make an Enlargement of a Photo