#### Question

# Can you help me in this reciprocal question please?

My son has a math question which I'm not understanding my closest guess is that the final answer will be a decimal it goes like this : Find a number which has a sum and a reciprocal of 20

#### Answers

Hello,

It goes something like this

x + 1/x = 20

Multiply both sides by x to get rid of fractions

x(x+ 1/x) = 20 (x)

x^2 + 1 = 20x

Subtract both sides by 20x

x^2 + 1 - 20 x = 20x - 20x

x^2 - 20x + 1 = 0

Then you have to use the quadratic formula

http://www.purplemath.com/modules/quadform.htm

Good luck!

#1

Im not sure how to answer this but the reciprocal of 20 is 1/20 (one-twentieth) Hope that helps.

#2