We know:

We have

Substitute:


Only 4 and 10 meet the requirements of the question.
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40 and 1 NOT, because 40 > 12
20 and 2 NOT, because 20 > 12
5 and 8 NOT because GCF(5, 8) = 1
Answer:
-102.4 = v
Step-by-step explanation:
-15.9 = -3.1 + v/8
Add 3.1 to each side
-15.9 + 3.1 = -3.1+3.1 + v/8
-12.8 = v/8
Multiply each side by 8
-12.8 * 8 = v/8*8
-102.4 = v
53-49=4
4 times 12=48. the unknown number is 48