At the bird park were some adults.
12 of the number of locals was equal to 2 times the number of tourists. When another 67 tourists entered and 40 locals left, the ratio of the number of locals to the number of tourists become 5 : 4. Find the number of locals at the bird park at first.
|
Make p the same (1)x4 = (3) |
Locals (1) |
Tourists (2) |
Make p the same (2)x5 = (4) |
Before |
16 u |
4 u |
1 u |
5 u |
Change |
- 160 |
- 40 |
+ 67 |
+ 335 |
After |
20 p |
5 p |
4 p |
20 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)
16 u - 160 = 5 u + 335
16 u - 5 u = 335 + 160
11 u = 495
1 u = 495 ÷ 11 = 45
Number of locals at the bird park at first
= 4 u
= 4 x 45
= 180
Answer(s): 180