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.

Friday, February 19, 2010

Nanyang Pri Sch 2009 P6 CA1 Math Paper 2 Q14

Mr Lim paid $134.40 for some jackfruits and pomeloes. The cost of the pomelo was 0.8 that of a jackfruit. A pomelo cost $5.60. If all the pomeloes cost $22.40 more than the jackfruits, how many fruits did he buy?

Solution



2 units --> $134.40 - $22.40 = $112
1 unit --> $112 divided by 2 = $56

Cost of Pomeloes
--> $56 + $22.40 = $78.40

Number of Pomeloes bought
--> $78.40 divided $5.60 (per pomelo)
= 14 pomeloes

Cost of of 1 pomelo is 0.8 of 1 jackfruit
Pomelo --> 8 units
Jackfruit--> 10 units

(Pomelo) 8 units --> $5.60
1 unit --> $5.60 divided by 8 = $0.70
(Jackfruit) 10 units --> 10 x $0.70 = $7

Number of Jackfruits bought
--> Total cost - cost of pomeloes
$134.40 - $78.40 = $56
$56 divided by $7 (per jackfruit) = 8 (jackfruits)

Total number of fruits
14 (pomeloes) + 8 (jackfruits) = 22 fruits

Answer: 22 fruits

No comments: