she is starting a balance for $300.She buys several dresses at $40 a piece . After her purchases she has $140 left on the gift card. How many dresses did she bu

Question

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Answer 1

Let's make our variable d = number of dresses.

Here's what we know:

40d + 140 = 300 (the cost of all the dresses bought plus the 140 left over equals the $300 starting point)

 

We start by subtracting 140 to both sides:

40d = 160 (this means that $160 has been spent on dresses)

Divide both sides by 40:

d = 4

 

So she bought 4 dresses.

 

Check:

4 * 40 + 140 = 300

160 + 140 = 300

300 = 300

 

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Answer 2

We know she started with $300.  Each time she buys a dress, her balance decreases.  She is left with $140.

 

 

Let x = the number of dresses she bought

 

 

Set up the equation.  Since the equation is a two step one, it will take 2 operations to solve for the variable x.

 

300 - 40x = 140

 

 

The first step is to subtract 300 on both sides of the equation to isolate the x terms.

 

-40x = -160

 

 

The second and final step is to divide both sides of the equation by -40.

 

x = 4

Answer 3

Her total purchase amount=$(300-140)=$160

Each dress costing $40 she bought total= ($160/$40)=4 dresses