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.

Saturday, February 28, 2009

Nanyang Pri Sch P6 CA1 2008 Math Q44

Sandy and Christine went to the bookshop and bought some stationary. Sandy bought 6 pens and 4 exercise books for $6.60. Christine bought 4 pens and 6 exercise books for $5.90. How much does each pen cost?

Solution


(Sandy) 6 pens + 4 books ----- $6.60 (x3)
(Christine) 4 pens + 6 books ----- $5.90 (x2)

(Sandy) 18 pens + 12 books ----- $19.80
(Christine) 8 pens + 12 books ----- $11.80

Difference in price between what Sandy and Christine paid:-
$19.80 - $11.80 = $8

Sandy paid $8 more because she bought 10 more pens than Christine:-
10 pens ----- $8
1 pen ----- $8 divided by 10 = $0.80

Answer: Each pen costs $0.80

1 comment:

Anonymous said...

eh stationery spell wrong hor