Question

Which calculations could be used to solve this problem?

There are 21 children at Corie's party. There are 2 times as many girls as boys at the party.

How many girls are at the party?

Choose all answers that are correct.

A.
Multiply 21 × 2. Divide the product by 3.

B.
Add 21 + 2. Divide the sum by 3.

C.
Divide 21 ÷ 3. Subtract the quotient from 21.

D.
Divide 21 ÷ 3. Multiply the quotient by 2.

Answer 1

Given:
total of 21 children
2 times as many girls as boys at the party.

Let x be the number of boys.

boy + girls = 21
x + 2x = 21
3x = 21
x = 21/3
x = 7 number of boys

2x = 2(7) = 14 number of girls.

C. Divide 21 ÷ 3. Subtract the quotient from 21.
D. Divide 21 ÷ 3. Multiply the quotient by 2.