Add and Subtract within 20

The sums and differences only reach 20 in this arithmetic worksheet. Scholars answer 10 simple number sentences, some involving two numbers and others with three. They choose the correct answer from a list on the right. There are the same number of answers as are there are problems. Consider requiring students to show their work so process of elimination doesn't become a strategy! There is not much to this worksheet; just solving addition and subtraction problems.