Question

Manali recorded -4°C temperature at 10pm and then it drooped by 2°C at 3am. What was the temperature at 3am? Next day it rose my 5°C by 11 am. what was the temperature at 11am?

Answer 1

Answer:

The temperature at 12 noon was 10oC above zero. If it decreases at the rate of 2oC per hour until midnight, at what time would the temperature be 8°C below zero? What would be the temperature at mid-night?

Solution:-

From the question is given that,

Temperature at the beginning i.e., at 12 noon = 10oC

Rate of change of temperature = – 2oC per hour

Then,

Temperature at 1 PM = 10 + (-2) = 10 – 2 = 8oC

Temperature at 2 PM = 8 + (-2) = 8 – 2 = 6oC

Temperature at 3 PM = 6 + (-2) = 6 – 2 = 4oC

Temperature at 4 PM = 4 + (-2) = 4 – 2 = 2oC

Temperature at 5 PM = 2 + (-2) = 2 – 2 = 0oC

Temperature at 6 PM = 0 + (-2) = 0 – 2 = -2oC

Temperature at 7 PM = -2 + (-2) = -2 -2 = -4oC

Temperature at 8 PM = -4 + (-2) = -4 – 2 = -6oC

Temperature at 9 PM = -6 + (-2) = -6 – 2 = -8oC

∴At 9 PM the temperature will be 8oC below zero

Then,

The temperature at mid-night i.e., at 12 AM

Change in temperature in 12 hours = -2oC × 12 = – 24oC

So, at midnight temperature will be = 10 + (-24)

= – 14oC

So, at midnight temperature will be 14oC below 0.