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If twice a number added to 3 is divided by the number plus 6, the result is three halves. Find the number.

1 Answer

11 votes

Answer:

3/2

Explanation:

Let x be the unknown number.

If twice a number added to 3: 2x+3

is divided by the number plus 3: (2x+3)/3

the result is three halves: (2x+3)/3 = 3/2

(2x+3)/3 = 3/2

Multiply both sides by 3:

2x + 3 = 9/2

Subtract 3 from both sides:

2x = 9/2 - 3 = 9/2 - 6/2 = 3/2

Divide both sides by 2:

x = 3/4

Check:

(2x+3)/3 = 3/2

(2*(3/4)+3)/3 = 3/2

(6/4 + 3)/3 = 3/2

(18/4)/3 = 3/2

6/4 = 3/2

3/2 = 3/2

Check!