At the museum were some adults.
12 of the number of tourists was equal to 2 times the number of locals. When another 9 locals entered and 44 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 |
12 u |
4 u |
1 u |
7 u |
Change |
- 132 |
- 44 |
+ 9 |
+ 63 |
After |
21 p |
7 p |
3 p |
21 p |
12 of the tourists = 2 times of the locals
1x22x2 of the tourists =
2x11x1 of the locals
Make the numerators the same. LCM of 1 and 2 is 2.
24 of the tourists =
21 of the locals
Tourists : Locals = 4 : 1
Make p the same.
(3) = (4)
12 u - 132 = 7 u + 63
12 u - 7 u = 63 + 132
5 u = 195
1 u = 195 ÷ 5 = 39
Number of locals at the museum at first
= 1 u
= 39
Answer(s): 39