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3 years ago
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Erna Wilderman
2 Answers
You WILL succeed with Will!
Depends on the question but basically: an inverse proportion is just 1/direct proportion.
So if two things have a direct proportion of 2 then their inverse proportion would be 1/2.
For example: 1) If n varies inversely as m and n=2 when m=21 then find:
a) the formula for n in terms of m:
f direct then n=km but this is inverse so n=k/m. Now find out k by substituting values you
know....2= k/21, multiply both sides by 21 and get k=21x2=42 and the formula is n=k/m so it is
n=42/m
b) the value of n given m=2
now we just substitute these values into our equation so n=42/m so n=42/2=21
c) the value of m given n=1
now we just substitute these values into our equation and n=42/m so 1=42/m which means m=42 when n=1 by cross multiplying
Hope this helps, just remember inverse proportion=1/direct proportion
I'm available for 1:1 private online tuition!
Click here to view my profile and arrange a free introduction.If x is inversely proportional to y, then your first step is to write an equation linking x and y as follows:
x = k/y
Then in the question you will be given a value of y for a given value of x. By substituting both of these into the above equation you can solve it to find k.
I advise that you then rewrite the equation replacing the k with the number you have just found.
Then you may be asked to find the value of x for a given value of y or vice versa, which means you need to substitute in the given value and solve the equation.
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