At the bird park were some adults.
12 of the number of locals was equal to 2 times the number of tourists. When another 72 tourists entered and 12 locals left, the ratio of the number of locals to the number of tourists become 8 : 7. Find the number of tourists at the bird park at first.
|
Make p the same (1)x7 = (3) |
Locals (1) |
Tourists (2) |
Make p the same (2)x8 = (4) |
Before |
28 u |
4 u |
1 u |
8 u |
Change |
- 84 |
- 12 |
+ 72 |
+ 576 |
After |
56 p |
8 p |
7 p |
56 p |
12 of the locals = 2 times of the tourists
1x22x2 of the locals =
2x11x1 of the tourists
Make the numerators the same. LCM of 1 and 2 is 2.
24 of the locals =
21 of the tourists
Locals : Tourists = 4 : 1
Make p the same.
(3) = (4)
28 u - 84 = 8 u + 576
28 u - 8 u = 576 + 84
20 u = 660
1 u = 660 ÷ 20 = 33
Number of tourists at the bird park at first
= 1 u
= 33
Answer(s): 33