Answer:
m=7
Step-by-step explanation:
1 blue jar = 21 marbles
1 blue jar = 3 red jars
Therefor
21 marbles= 3 red jars
(Now let m=1 red jar)
21= 3m
(Then sine we have 3m dived both sides by 3 to isolate the m)
21/3= 3m/3
7=m
The "one head and one tail" would be my best guess because you get one of each outcome, whereas the other two outcomes are two of the same outcome.
He just switched sides of the variables and numbers. Instead if adding the opposite.
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It will cost
$6.50 for four pounds of plums.
Hope this helps!