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If a number x is increased by 20% and t...

If a number x is increased by 20% and then reduced by 20 , it results in 160 .Instead , if the number x is rduced by 20% and increased by 20 then what will be the result?

A

`140`

B

`144`

C

`148`

D

`152`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, let's follow the same approach as the video transcript: ### Step 1: Set up the equation for the first scenario We know that when the number \( x \) is increased by 20% and then reduced by 20, it results in 160. First, we calculate 20% of \( x \): \[ 20\% \text{ of } x = \frac{20}{100} \times x = \frac{x}{5} \] Now, when \( x \) is increased by 20%, it becomes: \[ x + \frac{x}{5} = \frac{5x + x}{5} = \frac{6x}{5} \] Next, we reduce this result by 20: \[ \frac{6x}{5} - 20 = 160 \] ### Step 2: Solve the equation Now, we will solve the equation: \[ \frac{6x}{5} - 20 = 160 \] Add 20 to both sides: \[ \frac{6x}{5} = 160 + 20 \] \[ \frac{6x}{5} = 180 \] Now, multiply both sides by 5: \[ 6x = 180 \times 5 \] \[ 6x = 900 \] Now, divide both sides by 6: \[ x = \frac{900}{6} = 150 \] ### Step 3: Set up the equation for the second scenario Now, we need to find the result when \( x \) is reduced by 20% and then increased by 20. First, calculate 20% of \( x \): \[ 20\% \text{ of } x = \frac{x}{5} \] When \( x \) is reduced by 20%, it becomes: \[ x - \frac{x}{5} = \frac{5x - x}{5} = \frac{4x}{5} \] Now, we increase this result by 20: \[ \frac{4x}{5} + 20 \] ### Step 4: Substitute the value of \( x \) Now substitute \( x = 150 \): \[ \frac{4 \times 150}{5} + 20 \] Calculate \( \frac{4 \times 150}{5} \): \[ \frac{600}{5} = 120 \] Now add 20: \[ 120 + 20 = 140 \] ### Final Result The result when \( x \) is reduced by 20% and then increased by 20 is: \[ \boxed{140} \] ---

To solve the problem step by step, let's follow the same approach as the video transcript: ### Step 1: Set up the equation for the first scenario We know that when the number \( x \) is increased by 20% and then reduced by 20, it results in 160. First, we calculate 20% of \( x \): \[ 20\% \text{ of } x = \frac{20}{100} \times x = \frac{x}{5} ...
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