Answer:
12,7
Explanation:
Here's the solution to your question:
a) If the ratio of goldfish to angelfish is 3:5, there are 3x goldfish and 5x angelfish in the aquarium. Since the total number of fish is 32, we can write:
3x + 5x = 32
Simplifying the equation gives:
8x = 32
x = 4
Therefore, there are 3x = 3*4=12 goldfish in the aquarium.
b) When some angelfish were added into the aquarium, the ratio of goldfish to angelfish became 4:9. Let's say that y angelfish were added. Then, the total number of angelfish became 5x + y, and the total number of goldfish remained the same as 3x = 12. This gives the equation:
12/(5x + y) = 4/9
Cross-multiplying and simplifying the equation gives:
108 = 20x + 4y
Since we know that x = 4, we can substitute it into the equation and obtain:
108 = 20*4 + 4y
Simplifying further gives:
4y = 28
y = 7
Therefore, 7 angelfish were added to the aquarium.