Question

Adrian conducted a scientific experiment. For a certain time, the temperature of a compound rose 3 3/4 degrees every 1 2/3 hours. What was the rate, in degrees per hour, that the temperature of the compound rose?

Answer 1

Notice that the temperature rose 3 3/4 degrees every 1 2/3 hours and we are asked to calculate a RATE which involves a quotient.

Therefore we need to start by converting both mixed numbers into fractions, so as to be able to divide one by the other.

3 3/4 = 3 + 3/4 = 12/4 + 3/4 = 15/4

and

1 2/3 = 1 + 2/3 = 3/3 + 2/3 = 5/3

Now we can calculate the rate (degrees per hour, or degrees / hour) by dividing 15/4 by 5/3:

15/4 divided by 5/3 = 15/4 * 3/5

where we used the converting of a division of fractions as the multiplication of the first one times the reciprocal of the second one.

15/4 * 3/5 = 45 / 20 = 9 / 4 = 2.25 degrees per hour.