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Are carpet coast $15 per square metre. the total delivery charge is $21 peter buys n squared metres of carpet what is the expression which represents the total cost in $

The graph below shows the amount of money left in the school’s desk fund, f, after d desks have been purchased. for each new desk that is purchased, by how much does the amount of money left in the school’s desk fund decrease?

You eat 8 strawberries and your friend eats 12 strawberries from a bowl. there are 20 strawberries left. which equation and solution give the original number of strawberries?