B. 90. The perimeter is 30+30+15+15=90
Andrew is wanting to build a slide for his daughter's tree house in the backyard. The tree house is approximately 5 feet off the ground and he wants the slide to have a 30 degree angle with the ground. He will need to by 10 ft of sliding board.
Decimal is the dot used after the ones to show parts of one you normally see it in money. 1.50. The . between 1 and 50 is the decimal. Whats in front of the decimal is ones, tens, hundreds, etc and after the decimal is tenths, hundredths, etc.
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