幚我做幾條數(20分)

7. The marked price of a digital camera in shop A is $3 500 and the selling price is $2800. The marked price of the same digital camera in shop B is $3200 and the selling price is $2600. Which shop offers a larger discount%?


The discount in shop A is:
3500-2800
------------- x 100%
3500

700
=--------------- x 100%
3500
= 20%


The disconut in shop B is:
3200-2600
-------------- x 100%
3200

600
= --------- x 100%
3200

=18.75%

SO, Shop B offers larger discount.



8. A shop sells a toy at a 12% discount such that the discount is $300.
(a) What is the marked price of the toy?
(b) If the cost price of the toy is $2000, find the profit per cent



(a) Let y be the marked price of toy:
y x 12% = 300
y = $2500
Therefore, the marked price of toy is $2500.

(b) the profit per cent :
$2500-$2000
----------------- x 100%
$2000
= 25%

7. The marked price of a digital camera in shop A is $3 500 and the selling price is $2800. The marked price of the same digital camera in shop B is $3200 and the selling price is $2600. Which shop offers a larger discount%?
Ans. :
Shop A offers (1- 2800 / 3500)*100% = 20% discount
Shop B offers (1 - 2600 / 3200)*100% = 18.75% discount
Shop A offers a larger discount.

8. A shop sells a toy at a 12% discount such that the discount is $300.
(a) What is the marked price of the toy?
Ans. : Let X be the marked price,
then X(12%) = 300
=> X = 300 / 12% = 2500
(b) If the cost price of the toy is $2000, find the profit per cent
Ans. : Discounted price is 2500-300 = 2200
Profit is 2200 - 2000 = 200
Profit % is (200/2000) * 100% = 10%