Question #a3e2c

2 Answers
Oct 28, 2017

x = 17/36

Explanation:

We can set up an equation to solve the value of the number, x.

The number = x

Multiplying the number by 3 = 3x

Subtracting 2/3 from that = 3x - 2/3

The result is 3/4, so

3x - 2/3 = 3/4

We can then solve our equation:

3x - 2/3 = 3/4

Add 2/3 to both sides:

3x = 3/4 + 2/3

3x = 17/12

Divide both sides by 3 to get the value of x:

x = 17/36

You can then check your answer (optional):

17/36 * 3 = 17/12

17/12 - 2/3 = 3/4

Oct 28, 2017

17/36

Explanation:

Breaking the question down into its component parts.

A number ......................................................... x
is multiplied by 3 ...........................................3x
and 2/3 is subtracted from the number ....3x-2/3
The result is 3/4................................................3x-2/3=3/4

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The wording of this question could be tidied up a bit. There are issues with it.

color(blue)("Step 1 - isolate the term with "x" in it")

Add 2/3 to both sides turning the left hand side -2/3 into 0

color(green)(3x-2/3color(red)(+2/3)color(white)("dd")=color(white)("dd")3/4color(red)(+2/3)

3x+0=3/4+2/3

3xcolor(white)("ddd")=3/4+2/3
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color(blue)("Step 2 - simplify the right hand side")

Multiply by 1 and you do not change the value. However, 1 comes in many forms.

color(green)(3x=[3/4color(red)(xx1)]+[2/3color(red)(xx1)]

color(green)(3x=[3/4color(red)(xx3/3)]+[2/3color(red)(xx4/4)]

3x=color(white)("dd")9/12color(white)("ddd")+color(white)("ddd")8/12color(white)("ddd") = 17/12

3x=17/12
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color(blue)("Step 3 - isolate "x)

Multiply both sides by 1/3 - turns the 3 from 3x into 1 and 1xx x= x

x=17/12xx1/3 = 17/36

17 is a prime number so we can not simplify the fraction any further.