.
In this post, I will solve #2 and #3.
#2.
Each of 9 teams plays with all 8 other teams.
It gives the product of 9*8 = 72, which we should divide by 2,
since taking the product we count each game twice.
Solved.
#3.
The governing equation is
= 86 (average).
The solution is in one line
fourth quiz score x = 4*86 - (82 + 91 + 77) = 94. ANSWER
Solved.
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