At the concert hall were some adults.
13 of the number of locals was equal to 2 times the number of tourists. When another 9 tourists entered and 46 locals left, the ratio of the number of locals to the number of tourists become 7 : 2. Find the number of tourists at the concert hall at first.
| |
Make p the same
(1)x2 = (3) |
Locals
(1) |
Tourists
(2) |
Make p the same
(2)x7 = (4) |
| Before |
12 u |
6 u |
1 u |
7 u |
| Change |
- 92 |
- 46 |
+ 9 |
+ 63 |
| After |
14 p |
7 p |
2 p |
14 p |
13 of the locals = 2 times of the tourists
1x23x2 of the locals =
2x11x1 of the tourists
Make the numerators the same. LCM of 1 and 2 is 2.
26 of the locals =
21 of the tourists
Locals : Tourists = 6 : 1
Make p the same.
(3) = (4)
12 u - 92 = 7 u + 63
12 u - 7 u = 63 + 92
5 u = 155
1 u = 155 ÷ 5 = 31
Number of tourists at the concert hall at first
= 1 u
= 31
Answer(s): 31
