The answer would be 50 and 37.
50-37 = 13
50+37 = 87
I am pretty sure your answer will be 96783564.8, but it may need to be rounded. If I am wrong, I am sorry.
Hope this helps~!
So the answer is 30 packages but I did 25 times 20 = 500 and then 25 times 10 = 250
So. 30 = 750
100 free throws* (7 goals/ 10 free throws)= 70 goals.
If David attempts 100 free throws, he will be successful about 70 times~