Fill in the blanks.
The ratio of adults to children is 2 : 5.
The ratio of girls to boys is 2 : 7.
Use LCM and find the following.
- Number of adults = _____ u
- Number of girls = _____ u
- Difference in the number of boys and girls = _____ u
- Total number of people = _____ u
Adults |
Children |
2x9 = 18 u |
5x9 = 45 u |
|
Girls |
Boys |
9 |
2x5 |
7x5 |
18 u |
10 u |
35 u |
(a)
Change ratio into units.
Girls : Boys : Children
2 : 7 : 2 + 7
2 : 7 : 9
The number of children is the repeated identity.
LCM of 5 and 9 is 45.
Number of adults = 18 u
(b)
Number of girls = 10 u
(c)
Difference in the number of boys and girls
= 35 u - 10 u
= 25 u
(d)
Total number of people
= 18 u + 45 u
= 63 u
Answer(s): (a) 18; (b) 10; (c) 25; (d) 63