Jorge buys a cd. the total cost was $17.80 that included a 5% sales tax. what was the price of the cd?

Aswimming pool had 2.5 million liters of water in it. some water evaporated, and then the pool only had 22 million liters of water in it. what percent of the water evaporated?

David is spreading mulch on a triangular area of his flower bed. the coordinates of the vertices of the area are (1, 3), (9, 3), and (4, 6). what is the area of the triangle if each square has an area of 3 square feet?

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class