Answer:
1
Explanation:
(FIRST THING FIRST REMEMBER PEMDAS)
First you rewrite the number sentence with the clues you got.
2 x 4 - 21 / 3
Then you do 2x4 to get 8, then you rewrite the # sentence again
8 - 21 / 3
Next you divide 21 / 3 to get 7 and rewrite the sentence again
8-7
FINALLY you subtract 8-7 to get 1