<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:
$174.76
Step-by-step explanation:
205.60 205.60
x 0.15 ----> - 30.84
------------- Next ---------------
30.84 $174.76
Hope this helped!
Answer:
193 packets
Step-by-step explanation:
Each morning they order with a shipping fee of $10 daily.
Considering they order all 7 days of the week, so the total shipping fee for the week would be:
7 * $10 = $70
Their budget for the week is $554, out of which $70 is for shipping for the week, so remaining balance would be:
554 - 70 = $484
This 484 dollars are for coffee packets that cost $2.50 each, so the number of packets would be:
484/2.50 = 193.6
You can't order fractional packets so 193 packets is the max in this budget
Answer:
B. Y²⁴
Step-by-step explanation:
For perfect cubes, the exponents are a multiple of three. If yᵃ is a perfect cube, then a/3=k where k is a whole number.
Among the provided choices, the exponent of y²⁴ is divisible by 3.
24/3 = 8.
Thus y²⁴ is a perfect cube.