At the school carnival, students guessed how many marbles are in a jar. Marlo guessed 84 when it was actually 80. What percent of error did Marlo have?

5%

Step-by-step explanation:

Percent of error = × 100%

                           = 5%

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Lexi and Ann went shopping. Ann wondered how much tax she would have to pay on her purchase of $76. Lexi said, "They just charged me $17 in taxes when I bought these outfits for $200." How much will Ann pay in taxes?

Ann's taxes = × $76

                   = $6.46

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Every week Roseanne gets paid $100 plus a 5% commission on all of her sales. If she has $5,000 in sales, how much is her pay for the week?

5% commission = × $5000

                          = $250

Total pay = $250 + $100

                = $350

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Every week Kabore gets paid $100 plus 5% of his sales. How much does he need to sell if he wants to make $700 this week?

Amount of commission paid = $700 - $100

                                               = $600

5% of sales = $600

100% of sales = × $600

                       = $12 000

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Get-It-Done Depot has an ad for piping that reads:

“15 inches of pipe - only $2.00

Get 15% off the total when you buy more than 3 feet”

Mike needs 4 feet of piping. How much will it cost him?

4 feet = 48 inches

48 inches - × $2.00 = $6.40

Total after 15% off (since 4 feet is more than 3 feet so the discount is legible) - × $6.40 = $5.44

step-by-step explanation:

there is a formula i can give you:

it is r^2*n*sin(360/n) divided by 2 where r represents the "radius" and n is the number of sides.

plug them in:

(10sqrt(3))^2*6*sin(360/6) divided by 2

100*3*6*sin(60) divided by 2

900*sin(60)

900*sqrt(3)/2

450*sqrt(3)

approx is 779.4 cm^2