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Practice Problems

Solve for x

$\mathbf{\text{1)}}$ $0.45x+3=3.9$

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The answer is $x=2$

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$0.45x+3=3.9$

$100\times (0.45x+3)=\left(3.9\right)\times 100$

$45x+300=390$

$45x=90$

$x=2$

$\mathbf{\text{2)}}$ $0.5x+18=22.5$

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The answer is $x=9$

$\mathbf{\text{3)}}$ $43.5+0.2x=51.1$

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The answer is $x=38$

$\mathbf{\text{4)}}$ $15.35+2x=16.55$

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The answer is $x=0.6$

$\mathbf{\text{5)}}$ $8+.02x=10$

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The answer is $x=100$

$\mathbf{\text{6)}}$ $-3.5x=7$

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The answer is $x=-2$

See Related Pages

$\bullet \text{ Equation Calculator (Symbolab.com)}$
$$

$\bullet \text{ Solving Equations by Addition and Subtraction}$
$x+3=4\dots$

$\bullet \text{ Solving Equations by Multiplication and Division}$
$8x=48\dots$

$\bullet \text{ Solving Multi-step Equations}$
$3x+2=14\dots$

$\bullet \text{ Solving Equations with Variables on Both Sides}$
$3x+5=7x-3\dots$

$\bullet \text{ Solving Equations with Decimals}$
$43.5+0.2x=51.1\dots$

$\bullet \text{ Solving Equations with Fractions}$
$\frac{2}{5}x+\frac{2}{3}=\frac{8}{3}\dots$

About Andymath.com

Andymath.com is a free math website with the mission of helping students, teachers and tutors find helpful notes, useful sample problems with answers including step by step solutions, and other related materials to supplement classroom learning. If you have any requests for additional content, please contact Andy at tutoring@andymath.com. He will promptly add the content.

Topics cover Elementary Math, Middle School, Algebra, Geometry, Algebra 2/Pre-calculus/Trig, Calculus and Probability/Statistics. In the future, I hope to add Physics and Linear Algebra content.

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