Question

The temperature at 12 noon was 10°C above zero. ¡fit decreases at the rate of 2°C per hour until midnight. at what time would the temperature be 8°C below zero? What would be the temperature at midnight’?

Answer 1

The temperature at 12 noon = 10°C 

Given temperature = 8°C below zero = – 8°C

Difference between the temperature = 10 – (- 8°) = 18°C 

∴ Time lasted = 18 + 2 = 9 hours 

i.e., at 9 o’ clock the temperature would be – 8C 

At mid-night the temperature 

10 + 12(-2) = 10 + (- 24) = – 14°C