There were some children in a stadium.
14 of the children lined up in 10 short rows and
16 of the children lined up in 5 long rows. The remaining children did not line up. There are 6 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 |
5 |
Value |
1 u |
1 u + 6 |
Total value |
10 u |
5 u + 30 |
(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.
5 u + 30 = 2 p --- (2)
(1)
x2
20 u = 6 p --- (3)
(2)
x3
15 u + 90 = 6 p --- (4)
(3) = (4)
20 u = 15 u + 90
20 u - 15 u = 90
5 u = 90
1 u = 90 ÷ 5 = 18
Number of children who lined up
= 10 u + 5 u + 30
= 15 u + 30
= 270 + 30
= 300
Answer(s): (a)
712; (b) 300