Question

A number is increased by 10% and then decreased by 15%. Find the net increase or decrease percent

Answer 1

Hello!

Let the required number be 100

Then,

✓ Number is increased by 10 % :

⇒ 100 + (100 × 10) / 100

⇒ 100 + 10

= 110

✓ Number is decreased by 15 % :

⇒ 110 - (110 × 15) / 100

⇒ 110 - 16.5

⇒ 93. 5

Now,

✓ Net increase or decrease :

Original Number - New Number × 100 / 100

⇒ (100 - 93.5) × 100 / 100

⇒ ( 6.5 × 100) / 100

⇒ 6.5 %

∴ Net decrease is 6.5 %

Cheers!

Answer 2

$\textbf {Hey there, here is the solution.}$

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STEP 1: Define x:

Let x be the number.

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STEP 2: Find the number after it is increased by 10%

10% of x = 0.1x

number after increment = x + 0.1x = 1.1x

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STEP 3: Find the number after it is decreased by 15%

15% of 1.1x = 0.15 x 1.1x = 0.165x

Number after the decrement = 1.1x - 0.165x = 0.935x

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STEP 4: Find the decrease:

Decreased percentage = x -0.935x = 0.065x

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STEP 4: Find the percentage of the decrease:

Decreased percentage = 0.065x/1 x 100 = 6.5%

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Answer: The net decrease is 6.5%

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$\textbf {I hope it helps.}$