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29 votes
29 votes
The sum of a number and 4 times it’s reciprocal is 13/3. Find the number(s).

User Simon Ottenhaus
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1 Answer

14 votes
14 votes

Let the unknown number be "x"

We will write an algebraic equation from the word problem given. Then we will solve for "x".

Given,

Sum of number (x) and 4 times the reciprocal is 13/3

We can convert it into an algebraic equation:


x+(4*(1)/(x))=(13)/(3)

Now, let's solve for the unknow, x,


\begin{gathered} x+(4*(1)/(x))=(13)/(3) \\ x+(4)/(x)=(13)/(3) \\ (x^2+4)/(x)=(13)/(3) \\ 3(x^2+4)=13* x \\ 3x^2+12=13x \\ 3x^2-13x+12=0 \\ (x-3)(x-(4)/(3))=0 \\ x=3 \\ x=(4)/(3) \end{gathered}

The numbers are


\begin{gathered} 3 \\ \text{and} \\ (4)/(3) \end{gathered}

User Immad Hamid
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