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Dylan is evaluation the expression 13+19+7+10 at one step in his work, dylan rewrites the equation as 13+7+19+10 which property of addition must dylan have used when he evaluated the expression?

Aski resort is charging $37.50 to rent a snowmobile for 5 hours. at this rate what will be the cost for a family of 5 to rent snowmobiles for 3 hours on the first day of their vacation and 4 hours for on the last day of their vacation

The price of a box of 15 cloud markers is $12.70. the price of a box of 42 cloud markers is $31.60. all prices are without tax, and the price of the packaging is the same for any size. how much would 50 cloud markers in a box cost? write an equation which will tell the price p for the number n markers in the box.