Its 4 by the way cause it is
<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.
120/4=30. Remember its widthxlength. if you forget ask your teacher or look online for more help. Good luck.
The difference between the volume of the spheres is 3428.88 cubic feet
Explanation:
Given that one sphere has a radius of 11 feet.
A second sphere has a radius of 8 feet.
<u>Volume of the 1st sphere:</u>
The formula to determine the volume of the sphere is given by

Volume of the 1st sphere is given by




The volume of the 1st sphere is 5572.45 cubic feet.
<u>Volume of the 2nd sphere:</u>
Volume of the 2nd sphere is given by




The volume of the 2nd sphere is 2143.57 cubic feet.
<u>Difference between the volume of the two spheres:</u>
Difference = Volume of the 1st sphere - Volume of the 2nd sphere
= 5572.45 - 2143.57
Difference = 3428.88 cubic feet.
Hence, the difference between the volume of the spheres is 3428.88 cubic feet.
Answer: The number of letters that must be engraved for the costs to be the same is 125.
Step-by-step explanation:
Since we have given that

We need to find the number of letters.

Hence, the number of letters that must be engraved for the costs to be the same is 125.