Answer:

Step-by-step explanation:
Hey!
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Solution:
72 tropical fish and 5/9 sold.
72 / 9 = 8
8 * 5 = 40
72 - 40 = 32
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Answer:
There are 32 fish left in the tank!
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Hope This Helped! Good Luck!
12/x + 7 =13/x, where x is not 0;
<=> 12 + 7x = 13 <=> 7x = 1 <=> x = 1/7;
Answer:
1000
Step-by-step explanation:
Lets just say x is the bigger number. We can create two equations.
x + y = 70
x - y = 30
If we add these equations together, we get that:
2x = 100
and that
x=50
Plugging x back into any of the equations gets us that y = 20, so xy = 20*50 = 1000