80
Answer:
Step-by-step explanation:
<h3>
Answer: 28</h3>
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Explanation:
Method 1
Imagine a table with 8 rows and 8 columns to represent all possible match-ups. You can actually draw out this table or just think of it as a thought experiment.
There are 8*8 = 64 entries in the table. Along the northwest diagonal, we have each team pair up with itself. This is of course silly and impossible. We cross off this entire diagonal so we drop to 64-8 = 56 entries.
Then notice that the lower left corner is a mirror copy of the upper right corner. A match-up like AB is the same as BA. So we must divide by 2 to get 56/2 = 28 different matches.
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Method 2
There are 8 selections for the first slot, and 8-1 = 7 selections for the second slot. We have 8*7 = 56 permutations and 56/2 = 28 combinations.
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Method 3
Use the nCr combination formula with n = 8 and r = 2

There are 28 combinations possible. Order doesn't matter (eg: match-up AB is the same as match-up BA).
Notice how the (8*7)/2 expression is part of the steps shown above in the nCr formula.
Answer:
1122
Step-by-step explanation:
I’ll solve number 3.
You need to group the like terms. For example, -4n + 6n = 2n
8=2n
Now, we need to keep n by itself.
2n/2 = n
Whatever you do to one side, you need to do to the other.
8/2 = 4
So, in conclusion, n = 4.
I hope this helps for you to solve the rest!
Answer:
In total she works 21 hours and for the equation its gn=g+n
Step-by-step explanation:
got the equation i just put gn but that can be replaced with 21 since g and n both represent the number of hours fawzia works