Question

When the price of a machine was increased by 25%, the number of machine sold fell by 25%. What was the effect on the total sale of machines?

Hint:

In problems with percentage changes, break the problem down step-by-step using simple multiplication to calculate the final result.

Answer 1

Step 1: Understanding the problem.
Let the original price of the machine be \( P \), and the original number of machines sold be \( N \). The total sale before the price increase is \( P \times N \). After the price increase, the new price is \( 1.25P \), and the number of machines sold decreases by 25%, which means the new number sold is \( 0.75N \).
Step 2: Calculating the new total sale.
The new total sale is: \[ \text{New total sale} = 1.25P \times 0.75N = 0.9375 \times P \times N \] This is 93.75% of the original total sale.
Step 3: Conclusion.
The total sale of machines decreases by 6.25%.