Antonio has a total of 55 marbles. He has 15 green marbles and 12 red marbles. The rest of the marbles are blue. How many blue marbles does he have?

A student solves this problem by writing an equation. Which strategy could help check the student’s answer?
Check that the sum of the final answer, 12, and 15 is 55.
Check that the difference of 55 and the final answer is 12.
Check that the sum of the final answer, 27, and 15 is 55.
Check that the difference of 55 and the final answer is 15.

Question

Antonio has a total of 55 marbles. He has 15 green marbles and 12 red marbles. The rest of the marbles are blue. How many blue marbles does he have?

A student solves this problem by writing an equation. Which strategy could help check the student’s answer?
Check that the sum of the final answer, 12, and 15 is 55.
Check that the difference of 55 and the final answer is 12.
Check that the sum of the final answer, 27, and 15 is 55.
Check that the difference of 55 and the final answer is 15.

Hoodmemes · Answer

Ok so first add the green and red marbles together

$$15+12=27$$

Then subtract that from the total amount which is 55

$$55-27=28$$

Answer option A is correct

Its correct due to the fact its asking you to (ADD) the number of red marbles and the total amount of (green and blue marbles) to get the final product of 55 marbles.

ilovemathbutitshard · Answer

Thank you so much! I rly appreciate it

Hoodmemes · Answer

Ngl i was confused at first