Page 149 - Start Up Mathematics_6

3
Lalita bought m of ribbon.
4

+
Total length of ribbon =  2 3 
 m
 5 4 
8 + 15
= ( LCM of 5 and 4 = 20)
20
23 1
= 20 23
20 –20
3
= 1 20 m 3

1 1
Example 37: Pulkit was given 1 piece of a pizza and Dolly was given 1 piece of a pizza. Find
4 3
the total amount of pizza given to both of them.

1
Solution: Pulkit got 1 piece of the pizza.
4
1
Dolly got 1 piece of the pizza.
3
1
Total amount of pizza given to both = 1 + 1 1
4 3
1 1  1 1
= 1+ + 1+ = ( 11+ ) +  + 
4 3  4 3 

 1 1  1 3 1 4
2
= 2 +  +  =+  × + × 
 4 3   4 3 3 4 
 3 4  34+
2
= 2 +  +  =+ ( LCM of 3 and 4 is 12)
 12 12  12
7 7
= 2 + = 2
12 12
7 3
Example 38: A piece of wire m long broke into two pieces. One piece was m long. How long
8 4
was the other piece?
7
Solution: Length of the wire = m
8
3
Length of one piece = m
4
7 3 7 3 × 2
∴ Length of the other piece = – = –
8 4 8 4 × 2
7 6 7 – 6
= – =
8 8 8
1
= m
8

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