I need help on a percent proportion question.

Find 4% of 1,275.

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Apositive number a or the same number a increased by 50% and then decreased by 50% of the result?

The sum of 5consecutive even numbers is 100. what is the first number in this sequence?

Arestaurant offers delivery for their pizzas. the total cost the customer pays is the price of the pizzas, plus a delivery fee. one customer pays $23 to have 2 pizzas delivered. another customer pays $59 for 6 pizzas. how many pizzas are delivered to a customer who pays $86?