On Thursday, there were 20 more children than adults at the fair. On Friday, the number of children increased by 60% and the number of adults decreased by 80%. There were 77 people on Friday. How many adults were there on Thursday?
| |
Children |
Adults |
Total |
Comparing children
and adults at first |
20 more |
|
|
| Before |
5 u |
+ 20 |
5 u |
|
| Change |
+ 3 u |
+ 12 |
- 4 u |
|
| After |
8 u |
+ 32 |
1 u |
77 |
60% =
60100 =
35 60% x 20 =
35 x 20 = 12
20 + 12 = 32
80% =
80100 =
45 Total number of people on Friday
= 8 u + 32 + 1 u
= 9 u + 32
9 u + 32 = 77
9 u = 77 - 32
9 u = 45
1 u = 45 ÷ 9 = 5
Number of adults on Thursday
= 5 u
= 5 x 5
= 25
Answer(s): 25
