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.

Verified Answer :

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.