## Raffles Girls SA2 2013 Primary 4 – Are you looking for this question?

Jenny had some fiction and non-fiction books to sell. She had 160 more fiction books than non-fiction books.After selling half of her fiction books and half of her non- fiction books, she had 3 times as many fiction books as non-fiction books. How many books did Jenny have at first?

The question above is actually an over simplified version of the concept “more than/less than” usually tested in primary 5 and primary 6 with fractions and percentages. Solving such questions requires the use of a comparison model, redrawn in stages to help a student work towards her answer.

If your child had some difficulty doing the above question, you may want to expose him/her to similar questions such as the ones we have below.

Clone 1:

John has 360 more cookies than cakes.

He sold half of the cookies and cakes.

As a result, the number of cookies became thrice as many as the number of cakes.

How many cookies did John have at first?

Clone 2:

John has some marbles.

Mary has 120 more marbles than John.

John and Mary gave away a third of their marbles.

As a result, the number of marbles Mary had became twice as many as the number of marbles John had.

How many marbles did they have in total at first?

Clone 3:

He gave 20 beads to John.

After which, both Teddy and Alice proceeded to give 1/4 of their total number of beads away.

As a result, Teddy had thrice as many beads as Alice in the end.

How many beads did both Teddy and Alice have altogether in the end?