Ned moves a 450 square foot garden in 15 minuted

Precalculus question, image attached.

If you draw a card with a value of three or less from a standard deck of cards, i will pay you $43. if not, you pay me $11. (aces are considered the highest card in the deck.) step 1 of 2 : find the expected value of the proposition. round your answer to two decimal places. losses must be expressed as negative values.

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?