At the stadium were some adults.
13 of the number of locals was equal to 2 times the number of tourists. When another 40 tourists entered and 79 locals left, the ratio of the number of locals to the number of tourists become 7 : 3. Find the number of locals at the stadium at first.
|
Make p the same (1)x3 = (3) |
Locals (1) |
Tourists (2) |
Make p the same (2)x7 = (4) |
Before |
18 u |
6 u |
1 u |
7 u |
Change |
- 237 |
- 79 |
+ 40 |
+ 280 |
After |
21 p |
7 p |
3 p |
21 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)
18 u - 237 = 7 u + 280
18 u - 7 u = 280 + 237
11 u = 517
1 u = 517 ÷ 11 = 47
Number of locals at the stadium at first
= 6 u
= 6 x 47
= 282
Answer(s): 282