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.

Wednesday, January 02, 2008

Ai Tong School P5 Math CA1 2006 (Q38)

A handkerchief cost $4. A towel cost 3 times as much as the handkerchief. If Mrs tan paid $216 for the 28 items, how many handkerchiefs did she buy?

Solution




For every 1 towel Mrs Tan buys in place of 1 handkerchief, she has to pay “$8 more”.

If we assume all 28 items bought were handkerchiefs

$28 x 4 = $112.

But she paid $216. This means she paid $216 - $112 = $104 more.

$8 “more” ----- 1 (towel)

$1 “more” ----- 1 divide by 8 = 1/8

$104 “more” ----- (1/8) x 104 = 13 (towels)

If she bought 13 towels, the number of handkerchiefs bought was

28 items – 13 towels ---- 15 handkerchiefs

Answer: She bought 15 handkerchiefs.

No comments: