What is the base of a shape? like a triangle? ?

The salesperson earns a 5% commission on the first $5,000 she has in sales. the salesperson earns a 7.5% commission on the amount of her sales that are greater than $5,000. this month the sales person had $8,000 in sales. what amount of commission, in dollars, did she earn?

329 people went to an amusement park. $906 was made that day. $1.5 per kid. $4 per adult. how many kids and adults went?

Mary and roberto bought identical backpacks at different stores. mary's backpack originally cost $65 and was discounted 25%. roberto's backpack originally cost $75 and was on sale for 30% off on the original price. which backpack was the better buy?