At the museum were some adults.
13 of the number of tourists was equal to 2 times the number of locals. When another 33 locals entered and 66 tourists left, the ratio of the number of tourists to the number of locals become 7 : 3. Find the number of locals at the museum at first.
|
Make p the same (1)x3 = (3) |
Tourists (1) |
Locals (2) |
Make p the same (2)x7 = (4) |
Before |
18 u |
6 u |
1 u |
7 u |
Change |
- 198 |
- 66 |
+ 33 |
+ 231 |
After |
21 p |
7 p |
3 p |
21 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)
18 u - 198 = 7 u + 231
18 u - 7 u = 231 + 198
11 u = 429
1 u = 429 ÷ 11 = 39
Number of locals at the museum at first
= 1 u
= 39
Answer(s): 39