The total number of pieces of ribbons that were used in the skydiving act is 28 ribbons
What are Combinations?
The number of ways of selecting r objects from n unlike objects is:
The equation for combination is
ⁿCₓ = n! / ( ( n - x )! x! )
where
n = total number of objects
x = number of choosing objects from the set
Given data ,
The total number of skydivers in the plane n = 8 skydivers
Each skydiver was connected to each of the other skydivers with a separate pieces of ribbon
So , the number of choosing skydivers x = 2
Now , the total number of ribbons used is calculated by combination
So , the equation is
ⁿCₓ = n! / ( ( n - x )! x! )
Substitute the value of n and x in the equation , we get
⁸C₂ = 8! / ( ( 8 - 2 )! x 2! )
= 8! / ( 6! x 2! )
= 8 x 7 / 2 x 1
= 56 / 2
= 28 ribbons
Hence , The total number of pieces of ribbons that were used in the skydiving act is 28 ribbons
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Answer:
28
Step-by-step explanation:
If a ribbon connects two skydivers, and there are 8 skydivers total, then we can do 8C2, which is equal to (8*7)/2, which is equal to 28. An alternate solution is to think of it this way. Skydiver 1 is connected to everyone else, which is 7 other people. Skydiver 2 is connected to everyone else but Skydiver 1, which is 6 other people. This goes on until Skydiver 8 is already connected with everyone. So we have 7+6+5+4+3+2+1+0, which is also equal to 28.
Answer:
Step-by-step explanation:
Factor the left hand side as a difference of squares:
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:
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L
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Hopefully this helps!