Question

The temperature at 12 noon is 100°c. If the temperature decreases at the rate of 20°c per hour, what will the temperature be at 8 pm?

Answer 1

Answer:

The temperature at 12 noon = 10° C above zero

The temperature is decreasing at 2° C per hour

8° C below zero = – 8° C

So, total fall in temperature from 10° C to 0° C and from 0° C to – 8° C = 18° C

Since the temperature falls 2° C in every one hour.

Therefore, to decrease 18° C, time taken = 18/2 = 9 hours

The present time is 12 noon so, the time when the temperature is – 8° C= 12 noon + 9 hours

So, The time at which the temperature will be – 8° C = 9 PM

Thus, at 9 pm temperature would be 8°C below zero.

Later,

The temperature at 12 noon = 10°C

The temperature decreases by 2°C every hour

The temperature decrease in 12 hours = – 2°C × 12 = – 24°C

At midnight, the temperature will be = 10°C + (-24°C) = -14 °C

Therefore, the temperature at mid night will be 14°C below 0.

So, at 12 midnight the temperature will be – 14° C.

Answer 2

The decrease in rate of temperature is = 20°C per hr.

So, for 8 hr is the temperature will be = ( 20 × 8 )

= 160°C.

Now, we have to find the temperature at 8 p.m.

• So, temperature in 8p.m = ( Original Temperature – Decreased Temperature )°C.
• Original Temperature is 100°C, Decreased Temperature is 160°C.
• Now, ( 100 – 160 )°C = – 60°C.

So, The temperature at 8 p.m. is = – 60°C. This is yours required answer. Hope you like my answer. Thanks for asking the question. Once again welcome in Brainly.

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