Fill in the blanks.
The ratio of adults to children is 9 : 7.
The ratio of boys to girls is 1 : 4.
Use LCM and find the following.
- Number of adults = _____ u
- Number of boys = _____ u
- Difference in the number of girls and boys = _____ u
- Total number of people = _____ u
Adults |
Children |
9x5 = 45 u |
7x5 = 35 u |
|
Boys |
Girls |
5 |
1x7 |
4x7 |
45 u |
7 u |
28 u |
(a)
Change ratio into units.
Boys : Girls : Children
1 : 4 : 1 + 4
1 : 4 : 5
The number of children is the repeated identity.
LCM of 7 and 5 is 35.
Number of adults = 45 u
(b)
Number of boys = 7 u
(c)
Difference in the number of girls and boys
= 28 u - 7 u
= 21 u
(d)
Total number of people
= 45 u + 35 u
= 80 u
Answer(s): (a) 45; (b) 7; (c) 21; (d) 80