Hello!
You have already earned 12.25 dollars. So now, you need to earn $31.75. If each errand is $1.50, you can divide $31.75 by $1.50. You would get roughly 21.17. Since you can not do 21 errands and .17 of an errand, you would need to do about 22 errands to get the money you need, which is the $31.75. 1.50 times 22 is equal to thirty-three, so youd be getting about a dollar and 25 cents more than what you need. We can had 33 (what we earn from our 22 errands) to 12.25, which is what we already have, and we get 45.25! So you can earn more money than you need to earn.
Hope this helps, have an awesome day!