Answer:
78
Step-by-step explanation:
You take the original total: 60, and multiply it by 30 to get 1,800. You then divide 1,800 by 100 to get 18. 18 is your 30%. Now, you add the 30% to 60 getting your total number of ducks: 78.
The equation version:
[tex]\frac{a}{60} = \frac{30}{100}[/tex]
It is just proportions.