If three times a number added to 4 is divided by the number plus 4, the result is five halves

Question

Please solve this problem

Answer 1

The most important skill in solving word problems is being able to translate the words into mathematical symbols.
Once it's in symbol form, it's usually easier to solve.

 

unknown number (n)

times (multiply)

three times a number (3n)

three times a number added (3n+4)

number plus 4 (n+4)

result (=)

five halves (5/2)

 

leading to (3n+4)/(n+4)=5/2

 

solve the proportion by writing equal cross-products

2(3n+4)=5(n+4)

 

6n + 8 = 5n + 20

-5n -8  = -5n-8

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n = 12