Answer:
-12 3/5
Step-by-step explanation:
-4 3/10 - 8 3/10
The signs are the same so we add and then take the sign
4 3/10 + 8 3/10
Add the whole numbers
4+8 = 12
Add the fractions
3/10 + 3/10 = 6/10
Simplify the fraction
6/10 = 3/5
Put them together
12 3/5
Add the sign
-12 3/5
6/9=x/21
x=21*6/9
=126/9
x=14
A. The student added before multiplying.
If they had multiplied 6 and 4 first, the next step would have been too divide. But since they added first, they got 36/24 or 3/2 when the answer should be 13.
12 minutes because 80-20 is 60 and 60 divides by 5 is 12
