Big Ideas Math: Modeling Real Life, Grade 7
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Big Ideas Math: Modeling Real Life, Grade 7 View details
6. Simple Interest
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Exercise 1 Page 269

How do you calculate 20 % of $8?

$ 9.60

Practice makes perfect
In order to find the selling price of the pool noodle, we need to add the sales tax in dollars to the original price. Original price+ Sales tax= Selling priceFirst, we have to find the cost added by the tax, which is 20 % of $8. We can find the value of the sales tax by multiplying the original price by the tax rate.
$8* 20 %
$8* 0.2
$1.60
Finally, by adding $1.60 to $8, we get the final selling price. $8+ $1.60= $ 9.60