Answer:
250,000 to 700,000 parts
Step-by-step explanation:
For the lower ratio of 0.5, we have to get 0.5 flouride parts/1 gallon of water equivalent to (some fluoride parts)/ (500,000 gallons of water). we can multiply 500,000 by 0.5 to get 250,000 as our lower limit. Similarly, we can multiply 500,000 by 1.4 to get 700,000 as our upper limit
Answer:there is no "net below"
Step-by-step explanation:
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.