Gerri spends 1/21 of her money on pencils and 2/21 on paper. What fraction of her money does she spend. Give the answer in simplest form.

A. 1/7

B. 3/20

C. 4/21

D. 8/7

Gerri spends 1/7 (A).

Step-by-step explanation:

If Gerri spends 1/21 of her money on pencils and 2/21 of her money on paper, adding these two fractions together will give us the total fraction of her money that she spent. Since 1/21 and 2/21 have the same denominator, we can add the numerators to get 3/21. However, fractions must always be in simplest form, meaning if the numerator (top number) and denominator (bottom number) can both be divided evenly by the same factor, then the fraction can be simplied to lower numbers. In this case the number 3 and the number 21 can both be divided evenly by 3: (3:3) / 21:3) = 1/7.