Let the total amount of money received from selling chairs on Saturday be 100 units.

Number of chairs sold on Sunday
= 150% of Saturday's chairs.

If the price was kept the same as on Saturday, the total amount received on Sunday would = 150 units.

However, the amount received only increased by 25%
→ 125 units

From this, we can find the price of a chair on Sunday as a percentage of Saturday's price.


125 units/150 units x 100%
= 5/6 x 100%
= 83⅓ % or ≈ 83.33%

This also means the price on Sunday was 5/6 of Saturday's.

So price of chair sold on Sunday
= $75 x 5/6
= $62.50

b) percentage decrease in the price
= 100% - 83.33%
= 16.67%
= 16.7% (1 decimal place)

Another approach to the question :

Increase in number of chairs by 50%
means no. of chairs sold on Sunday was 150% of that on Saturday.

150% = 150/100 = 3/2 of Saturday.

However amounted collected only increased by 25%. This means amount collected on Sunday is 125% of Saturday.

125% = 125/100 = 5/4 of Saturday

So, to find price as a fraction of Saturday's price, take the fraction of amounted collected on Saturday and divide by the fraction of no. of chairs sold on Saturday.

5/4 ÷ 3/2
= 5/4 x 2/3
= 10/12
= 5/6
So the price on Sunday is 5/6 that of Saturday.

5/6 x $75 = $62.50




Another way to see it :

Let's assume the number of chairs sold on Saturday be 2 and number of chairs sold on Sunday be 3.

5/4 = 15/12

So the amount of money received on Sunday can be seen as 15 units worth
The amount received on Saturday is 12 units worth.

15 units ÷ 3 chairs = 5 units per chair
12 units ÷ 2 chairs = 6 units per chair


So price on Saturday = 6 units per chair
Price on Sunday = 5 units per chair

6 units = $75
1 unit = $75 ÷ 6
= $12.50

5 units = $12.50 x 5 = $62.50




b)

1 - 5/6 = 1/6

The price decreased by 1/6 on Sunday.

1/6 x 100%
= 100/6 %
= 16.6666666666..... %
≈ 16.7% (1 decimal place)