Question

On a day in Srinagar, the temperature at '$6\mathrm{pm}$‘ was ’$2°\mathrm{C}$' but at '$11\mathrm{pm}$‘, it dropped to ’$-5°\mathrm{C}$'. By how many degrees celsius does the temperature fall?

Answer 1

Step: Finding the temperature fall.

Given,

$\Rightarrow$ The temperature at $6\mathrm{pm}$ $=2°\mathrm{C}$

$\Rightarrow$The temperature at $11\mathrm{pm}$$=-5°\mathrm{C}$

$\Rightarrow$The fall in temperature$=\mathrm{temperature}\mathrm{at}11\mathrm{pm}-\mathrm{temperature}\mathrm{at}6\mathrm{pm}$ ($\because$ Fall or rise in temperature is calculated by taking the difference)

$=-5-2$

$=-5+\left(-2\right)$ ($\because$ In subtraction, we add the additive inverse of the number to be subtracted)

$=-7°\mathrm{C}$ ($\because$ The sum is negative when both the integers are negative)

Here,The ‘$-$’ sign indicates that the temperature is falling.

Therefore, the temperature has fallen by $7°\mathrm{C}$.