There were some children in a safari park. ¹₄ of the children lined up in 10 short rows and ¹₆ of the children lined up in 6 long rows. The remaining children did not line up. There are 10 more children in each long row than each short row.
(a) What fraction of the children did not line up?
(b) How many children lined up?

	Short rows	Long rows
Number	10	6
Value	1 u	1 u + 10
Total value	10 u	6 u + 60

(a)
Fraction of children who did not line up
= 1 - ¹₄  - ¹₆  
= 1 - ³₁₂ - ²₁₂
= 1 - ⁵₁₂
= ⁷₁₂

(b)
³₁₂ of the children lined up in short rows.

10 u = 3 p --- (1)

²₁₂ of the children lined up in long rows.

6 u + 60 = 2 p --- (2)

(1)_x2
20 u = 6 p --- (3)

(2)_x3
18 u + 180 = 6 p --- (4)

(3) = (4)
20 u = 18 u + 180
20 u - 18 u = 180
2 u =  180

1 u = 180 ÷ 2 = 90

Number of children who lined up
= 10 u + 6 u + 60
= 16 u + 60
= 1440 + 60
= 1500

Answer(s): (a) ⁷₁₂; (b) 1500