A clown sells large balloon animals for $25 each. Small balloon animals sell for $10 each. Jordan is buying 2 large balloon animals and x small balloon animals. Let y represent the total cost Jordan must pay in dollars. Part 1: Write an equation in slope-intercept form to model this description. Part 2: What is Jordan’s total cost if she purchases 4 small balloon animals? Show your work.

 Part 1: y =10x+50

Part 2:  Jordan’s total cost = $90

Step-by-step explanation:

Given: Price of each large balloon = $25

Price of each small balloon = $10

Price of 2 large balloons = 2 (Price of each large balloon)

= $2 (25)

= $50

Part 1: Total cost = (Number of small balloons)(Price of each small balloon)  +  (Number of large balloons)(Price of each large balloon)

Let x = Number if small balloons , y=  total cost Jordan must pay in dollars.

Then, y= (x)(10)+(2)(25)

⇒ y =10x+50

Part 2: If she purchases 4 small balloon animals, put x=4

Then, y= 10(4)+50=40+50= 90

i.e. Jordan’s total cost = $90

step-by-step explanation:

30% of $420 is 0.30($420) = $126 and $420 + $126 = $546.

or, 130% of $420 is 1.3($420) = $546.

notice that this is not the $600 original list price with which we started.

why doesn't this work?

the method does not work because 30% of $420 is not the same amount as the 30% of $600. it may seem obvious when stated this way, but it is a very common error made on problems of this type. we cannot just use the same percent and get back to the original amount because we are taking that percent of a different value.

to work problems of this type correctly, it is generally best to write an equation for the situation and then solve.

example: since (100% – 30%)(original price) = (sale price)

70% of the   (original price) is $420.

0.7x   = 420

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x = 600

the original cost was $600.

we may also solve this problem using the two-step method. working the problem in two steps requires us to use more algebra skills. we have to know that x = 1x (identity property of multiplicationtext annotation indicator) and that 1x – 0.3x = 0.7x (subtracting like terms). then we solve the problem as follows:

(original price) – 30%(original price) = sale price

x – 0.3x = 420

0.7x = $420

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x = 600

the original cost was $600.  

note that with both of the above methods we do obtain the correct original amount.

example: after a 5% pay raise, hermione is earning $22,680 per year. what was she earning before the pay raise?

105% of (original salary) = current salary

1.05x = 22,680

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x = 21,600

hermione earned $21,600 per year before the pay raise.

this is an example so maybe you will get how to at least do it!

the answer is 8

step-by-step explanation:

3.14 x 8x8