Question

Which problem situation could be solved using the open sentence below?

24 - k = ?
A.Mrs. Garcia took 24 science papers home to grade. She graded k science papers before dinner. How many science papers did she have to grade after dinner?

B.Mrs. Garcia took 24 science papers and k reading papers home to grade. How many papers did she have to grade?

C.Mrs. Garcia had k science papers to grade. She now has 22 left to grade. How many papers did she grade already?

D. Mrs. Garcia has 22 science papers and 22 reading papers to grade. If she has k papers to grade in all, how many papers does she have to grade?

Answer 1

The answer is A.

You use the deduction method - C and D clearly can't be the correct answers since there's only 22 papers there, somehow, so the only valid potential answers are A and B.

B cannot be it, since she took k papers at home and took extra 24, meaning that would be 24 + k.

So the only possible answer is A, since she has 24 papers and has already done k amount of papers, meaning it's reduction - 24-k = ?.