This blog is managed by Song Hock Chye, author of Improve Your Thinking Skills in Maths (P1-P3 series), which is published and distributed by EPH.

## Tuesday, September 22, 2009

### Raffles Girls Pri Sch 2007 PSLE Math Prelim Q48

Valley Department Store sold a dress for \$585. This was 17% more than the price of a similar dress in Wiki Department Store. During a sale, both stores offered same percentage discount on the dress. Christine bought the dress in Wiki Department Store and found that she paid \$68 less than the discounted price in Valley Department Store.

(a) Find the price of the dress in Wiki Department Store before the sale.
(b) What is the percentage discount given during the sale?

Solution

(a)

Valley ----- 100% + 17% = \$585
117% ----- \$585
1% ----- \$585 divided by 117 = \$5

(Wiki) 100% ----- 100 x \$5 = \$500

(b)
Before discount

\$85 is the difference in price between Valley and Wiki before the discount. After the discount, the difference was \$68.

\$85 - \$68 = \$17
Discount ----- (\$17/\$85) x 100% = 20%