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1. Reciprocal meaning? How would i calculate the reciprocal of 2.5?
2. The reciprocal is 1/x so the reciprocal would be 1/2.5 which is 2/5 because when you multiply this by the original you should get 1.

So: The reciprocal of x is 1/x. When multiplied: 1/x * x = 1
3. (Original post by questioner...)
Reciprocal meaning? How would i calculate the reciprocal of 2.5?
I don't know the exact meaning of a reciprocal, but it basically means turning the given number into an upside down fraction (if that makes any sense).

So, the reciprocal of 2.5, which in a fraction term is 5/2, will be 2/5.
4. (Original post by questioner...)
Reciprocal meaning? How would i calculate the reciprocal of 2.5?

A reciprocal value is a value you multiply by to get 1. It's also commonly seen as flipping the top and bottom of a fraction. For example the reciprocal of 2 (also represented as 2/1) is 1/2.

Write 2.5 as a fraction. Flip said fraction. You now have a reciprocal. To check it works multiply the 2 fractions together to get 1. And that's the simple explanation of reciprocals that can also be found by Googling it.
5. (Original post by questioner...)
Reciprocal meaning? How would i calculate the reciprocal of 2.5?
A reciprocal of a number is defined as the number that when multiplied by the initial number gives 1.

So if x is a number and x* is its reciprocal, xx*=1.

Hence x*=1/x.

So for any number x, to calculate its reciprocal, just take 1 and divide it by x.

So the rest reciprocal of 2.5 is 1/2.5=0.4 because 2.5*0.4=1.
6. (Original post by questioner...)
Reciprocal meaning? How would i calculate the reciprocal of 2.5?
Lots of ways to look at it as seen above
the reciprocal of a number is that number to the power of -1
The reciprocal of 2 is 1/2 or 0.5

The reciprocal of 2.5 is the fraction 1/2.5 - though you'd not leave the answer as a fraction with a decimal number in it.
An alternative approach is to write it the number first as a top heavy fraction
2.5 = 5/2 as a fraction.
The reciprocal would then be 2/5

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