Question

Число уменьшили сначала на 25%, а затем увеличили на 30%. Как и на сколько изменилось число?

Answer 1

X-x*0,25+x*0,3=1,05X
Ответ:на 5%

Answer 2

Calculation of Change in Number

To calculate the change in the number after it was first decreased by 25% and then increased by 30%, we can use the following steps:

1. Decrease by 25%: When a number is decreased by 25%, it is multiplied by 0.75 (100% - 25% = 75% or 0.75). 2. Increase by 30%: When a number is increased by 30%, it is multiplied by 1.30 (100% + 30% = 130% or 1.30).

Let's denote the original number as X.

Calculation Steps

1. Decrease by 25%: X * 0.75 2. Increase by 30%: (X * 0.75) * 1.30

Now, let's calculate the change in the number using these steps.

Calculation

1. Decrease by 25%: X * 0.75 2. Increase by 30%: (X * 0.75) * 1.30

The change in the number after being first decreased by 25% and then increased by 30% is given by the expression (X * 0.75) * 1.30.

Result

The number changed by (X * 0.75) * 1.30 after being first decreased by 25% and then increased by 30%.

This calculation ensures that the change in the number is accurately determined based on the given percentage changes.