problem solving

2.  2 files cost as much as 3 markers. Mrs Wu
bought 8 files and 8 markers. She gave the
cashier $50 and received a change of $22.
Find the cost of each marker.
Cost of files and markers  $50 - $22 = $28
2 f = 3 m
8 f = 12 m
12 m + 8 m = $28
20 m = $28
1 m = $28 ÷ 20
= $1.40
The cost of each marker is $1.40.

3. 1) Ailin bought 5 squash rackets and 2 tennis
rackets. Each tennis racket costs 4 times as
much as a squash racket. If Ailin paid $ 364 for
all the items, how much was the cost of a tennis
racket?
2) Mrs Tan paid $4800 for 3 TV sets and 4 DVD
players. Each TV set cost twice as much as each
DVD player. Find the cost of each TV set.
3) Alicia bought 2 kg of sugar and 3 kg of coffee
powder at an average price of $6.36. Judy
bought 1 kg of sugar and 2 kg of coffee powder
at an average price of $6.80. Find the cost of 1
kg of coffee powder.

4.  The ratio of oranges to guavas is 1:5. If 387 guavas are
added, the ratio of oranges to guavas will be 2:19. How
many oranges are there?
 Before: After:
 O : G O : G
 1 : 5 2 : 19

 2 : 10

 19u – 10u = 9u
 9u =387
 1u = 43
 2u = 86
x2

5. 1) The ratio of apples to guavas is 3:11. If 184
guavas are added, the ratio of apples to guavas
will be 1:5. How many apples are there?
2) The ratio of the number of tennis rackets to the
number of squash rackets was 4:7. After 76
squash rackets were sold, the ratio became 4:3.
How many tennis and squash rackets were there
altogether at first?
3) The ratio of Yan Jie’s number of stamps to
Rayyaan’s number of stamps was 5:4. After Yan
Jie gave away 207 stamps, the ratio became 2:4.
Find the total number of stamps both boys had at
first.