Rational Number Word Problems Test, Question 2 by Jay Jay

2. In a cold storage chamber, the temperature drops 5.2C every 10 minutes. If the temperature is initially 19C, what is the temperature in the chamber after 1½ hours?

Important things we know : 

5.2°C down every 10 minutes. (x9 = 90 minutes)

1½ hours  90 Minutes (90 ÷ 10 = 9)

Temperature is 19°C

19°C - (5.2°C x 9)    = 19°C - 46.8°C

                                  = -27.8°C

Therefore, the temperature in the cold storage chamber after 1½ hours is, -27.8°C