Question

How did the temperature change if: at first it decreased by 60% and then increased by 80%. PLEASE NEED HELP!

Answer 1

The temperature decreased by 28%

Step-by-step explanation:

How did the temperature change if :

• At first it decreased by 60%
• Then increased by 80%

Assume that the temperature before decreasing is 100%

∵ The temperature before decreasing = 100%

∵ It decreased by 60%

→  Before decreasing  :  decreasing  :    after decreasing

→  100%                         :  60%              :    100% - 60% = 40%

∴ The temperature after decreasing = 40%

Assume that the temperature after decreasing is 100%

∵ The temperature after decreasing = 100%

∵ It increased by 80%

By using the ratio method

→  After decreasing  :  increasing  :    after increasing

→  100%                      :  80%             :   100% + 80% = 180%

→  40%                        :                       :   x%

By using cross multiplication

∴ 100% × x% = 40% × 180%

- Divide both sides by 100%

∴ x% = $\frac{(40)(180)}{100}$

∴ x% = 72%

∵ At first the temperature = 100%

∵ At last the temperature = 72%

∵ The first the temperature > the last the temperature

∴ The decreasing in temperature = 100% - 72% = 28%

The temperature decreased by 28%

Learn more:

You can learn more about ratio in brainly.com/question/2707032

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