A1. At a party, if each kid took one apple from the fruit bucket then 7 apples would still remain in the bucket. However, if each kid had an appetite for two apples, the supply would be 16 apples short. How many kids were at the party?
Solution: Let $a$ and $k$ be the number of apples and kids respectively. We have $a-k=7$ and $a-2 k=-16$. Then $a=7+k$ and $k=7+16=23$.

Answer: 23 $\square$