His brother would be 7 years old.
Answer:
16 students got an A
Step-by-step explanation:
Set up an equation to compare the ratio to the scores:

Cross multiply:
80 = 5x
Divide each side by 5:
x = 16
Now, check if 
16/8 = 2
40/8 = 5
The ratios are the same! Therefore, 16 students got an A!
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This is a combination question
Hope this helps
Answer:
A real number
Step-by-step explanation:
(-6) + 3 = -3 ;
The negative integer is -6; the positive integer is 3.