Page 92 - ICSE Math 5

7 3
Example 32: A wire of length m broke into two pieces. One piece was m long. How long was
8 4
the other piece?
7
Solution: Total length of wire = m
8
3
Length of one piece of wire after it broke into two pieces = m
4
7 3
 Length of the other piece of wire = – m (L.C.M. of 8 and 4 is 8.)
8 4

7 × 1 3 × 2
= – m
8 × 1 4 × 2

7 6 7 – 6 1
= – m = m = m.
8 8 8 8

1
So, the length of the other piece of wire was m.
8
Word Problems on Multiplication and Division of Fractions

1
Example 33: At a gaming station, of the games are racing games. Among these racing games,
2
2 are car racing games. What fraction of games at the gaming station are car racing
5
games?
1
Solution: Fraction of racing games at the gaming station =
2
2
Out of these, fraction of car racing games =
5
 Fraction of car racing games at the gaming station

2 1
= of
5 2
1
2 1 2  1 1  1 1
=  = = =
5 2 5  2 5  1 5
1
1
So, at the gaming station, of all the racing games are car racing games.
5
2
Example 34: A painter used of paint from a can to colour two rooms. What fraction of paint did
5
he use from the can to colour each room, if he used the same amount of paint to

colour each room?
2
Solution: Fraction of paint used by the painter to colour 2 rooms =
5
2 2 2
Fraction of paint used by the painter to colour 1 room = ÷ 2 = ÷
5 5 1
1
2 1 2  1 1  1 1
= × = = =
5 2 5  2 5  1 5
1 1
So, the painter used of paint from the can to colour each room.
5

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