PSLE Ken spent
13 of his money to buy 3 identical pens. He spent the rest of his money to buy another 5 such pens and 2 identical pencils.
- What fraction of Ken's money was spent to buy the 2 pencils? Give your answer in the simplest form.
- For every 4 pencils bought, 1 additional pencil was given free. How many pencils would Ken get in total if he were to spend all his money to buy pencils only?
(a)
Cost of 3 pens =
13 of his money
Cost of 1 pen
=
13 ÷ 3
=
13 x
13 =
19 of his money
Cost of 5 pens
= 5 x
19 =
59 of his money
Fraction of Ken's money spent to buy the 5 pens and 2 pencils
= 1 -
13 =
23 Fraction of Ken's money spent to buy the 2 pencils
=
23 -
59 =
69 -
59 =
19 (b)
19 of Ken's money = 2 pencils
99 of Ken's money = 9 x 2 = 18 pencils
Number of free pencils
= 18 ÷ 4
= 3 r 3
Total number of pencils that Ken would get
= 18 + 3
= 21
Answer(s): (a)
19; (b) 21