At the museum were some adults.
13 of the number of tourists was equal to 2 times the number of locals. When another 80 locals entered and 70 tourists left, the ratio of the number of tourists to the number of locals become 8 : 5. Find the number of locals at the museum at first.
|
Make p the same (1)x5 = (3) |
Tourists (1) |
Locals (2) |
Make p the same (2)x8 = (4) |
Before |
30 u |
6 u |
1 u |
8 u |
Change |
- 350 |
- 70 |
+ 80 |
+ 640 |
After |
40 p |
8 p |
5 p |
40 p |
13 of the tourists = 2 times of the locals
1x23x2 of the tourists =
2x11x1 of the locals
Make the numerators the same. LCM of 1 and 2 is 2.
26 of the tourists =
21 of the locals
Tourists : Locals = 6 : 1
Make p the same.
(3) = (4)
30 u - 350 = 8 u + 640
30 u - 8 u = 640 + 350
22 u = 990
1 u = 990 ÷ 22 = 45
Number of locals at the museum at first
= 1 u
= 45
Answer(s): 45