Joe buys groceries for his grandfather the groceries cost $42 plus 5% tax joe wants to know the total cost of the groceries including tax how much sales tax does joe pay on the groceries

its on iready

Work Shown:

5% = 5/100 = 0.05

5% of 42 = 0.05*42 = 2.10

tax = $2.10

total cost including tax = $42 + $2.10 = $44.10

An alternative is to multiply 42 by 1.05 to get

1.05*42 = 44.10

We get the same answer. The 1.05 refers to 1 + 0.05 where the "1" is 100% and the 0.05 is 5%, so the two combine to 105%, meaning the total cost is 105% of the cost before tax is considered.

look a the sides they are perpendicular