At the stadium were some adults.
12 of the number of locals was equal to 2 times the number of tourists. When another 11 tourists entered and 56 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 |
12 u |
4 u |
1 u |
7 u |
Change |
- 168 |
- 56 |
+ 11 |
+ 77 |
After |
21 p |
7 p |
3 p |
21 p |
12 of the locals = 2 times of the tourists
1x22x2 of the locals =
2x11x1 of the tourists
Make the numerators the same. LCM of 1 and 2 is 2.
24 of the locals =
21 of the tourists
Locals : Tourists = 4 : 1
Make p the same.
(3) = (4)
12 u - 168 = 7 u + 77
12 u - 7 u = 77 + 168
5 u = 245
1 u = 245 ÷ 5 = 49
Number of locals at the stadium at first
= 4 u
= 4 x 49
= 196
Answer(s): 196