There were
57 as many adults as children on a bus. At the first bus stop, 10 adults and 10 children boarded the bus. There were then
56 as many adults as children. How many adults were on the bus at first?
|
Adults |
Children |
Difference |
Before |
5x1 = 5 u |
7x1 = 7 u |
2x1 = 2 u |
Change |
+ 10 |
+ 10 |
|
After |
5x2 = 10 u |
6x2 = 12 u |
1x2 = 2 u |
Since equal number of adults and children boarded the bus, the difference in the number of adults and children at first and in the end remains the same. LCM of 2 and 1 is 2.
Number of adults who boarded the bus
= 10 u - 5 u
= 5 u
5 u = 10
1 u = 10 ÷ 5 = 2
Number of adults at first
= 5 u
= 5 x 2
= 10
Answer(s): 10