At the zoo were some adults.
12 of the number of locals was equal to 3 times the number of tourists. When another 75 tourists entered and 60 locals left, the ratio of the number of locals to the number of tourists become 8 : 7. Find the number of tourists at the zoo at first.
| |
Make p the same
(1)x7 = (3) |
Locals
(1) |
Tourists
(2) |
Make p the same
(2)x8 = (4) |
| Before |
42 u |
6 u |
1 u |
8 u |
| Change |
- 420 |
- 60 |
+ 75 |
+ 600 |
| After |
56 p |
8 p |
7 p |
56 p |
12 of the locals = 3 times of the tourists
1x32x3 of the locals =
3x11x1 of the tourists
Make the numerators the same. LCM of 1 and 3 is 3.
36 of the locals =
31 of the tourists
Locals : Tourists = 6 : 1
Make p the same.
(3) = (4)
42 u - 420 = 8 u + 600
42 u - 8 u = 600 + 420
34 u = 1020
1 u = 1020 ÷ 34 = 30
Number of tourists at the zoo at first
= 1 u
= 30
Answer(s): 30
