Page 84 - ICSE Math 6

1 5 1 3
RHS = 5 ×2 + 5 ×2
4 6 4 4
5×4 1 2×6 5+ + 5×4 1 2×4 3+ +
= × + ×
4 6 4 4
21 17 21 11 7 21 ×17 21×11 119 231
= × + × = + = +
4 6 4 4 4× 6 2 4×4 8 16
119×2 231+ 238 231+ 469 5
= = = = 29
16 16 16 16

\ LHS = RHS

1 1    1   
Example 27: Simplify 3 of + 4 ÷  4× 4– 4 –    .


3 2    5   
+
1 1    1    3×3 1 1    4×5 1  −  
Solution: 3 of + 4 ÷  4× 4– 4 –    = of + 4 ÷ 4× 4 –     



3 2    5    3 2    5   
10 1  19 
= of + 4 ÷  4× 4 –
{ }
3 2  5 
10 1  { 4×5 19  −
= of + 4 ÷  4× }
3 2  5 
10 1  1 10 1 4
= of + 4 ÷  4×  = of + 4 ÷
3 2  5 3 2 5

10 5 1 4 5 4
= × + 4 ÷ = + 4 ÷
3 2 1 5 3 5

5 1 5 5
= + 4 × = + 5
3 4 1 3
5 + 5 × 3 20 2
= = = 6
3 3 3
Word Problems

2
Example 28: In a class, of the students are boys. If the total number of students is 66, then find
11
the number of boys and girls in the class.
2
Solution: Given that of the students are boys.
11
2 2 2× 66 6
So, the number of boys in the class = of 66 = × 66 = = 12
11 11 11 1
Thus, there are 12 boys in the class.

Total number of students = 66
Number of boys = 12

\ Number of girls = 66 – 12 = 54

68