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.

Sunday, December 16, 2007

Anglo-Chinese School (Primary) P5 SA2 2006 Math Question (Q43)

During a travel fair, 120 families chose Switzerland as their holiday destination. 80% of the remaining families chose Australia while the rest chose Japan. If 10% of all the families at the travel fair chose Japan, how many families were there at the travel fair?

Solution

20% of remaining families ----- 10% of all families

10% of remaining families ----- 10% divided 2 = 5% of all families

(Australia) 80% of remaining families ----- 8 x 5% = 40 of all families

(Australia) 40% of all families + (Japan) 10% of all families ----- 50% of all families

Therefore Switzerland is also ----- 50% of all families, which makes up 120 families.

50% ----- 120 families

100% ----- 120 families x 2 = 240 families

Answer: There were 240 families at the travel fair.