The equation P = 2.5m + 35 represents the price P (in dollars) of a bracelet, where m is the cost of the materials (in dollars). The price of a bracelet is $115. What is the cost of the materials?
The cost of the materials is $

You can ride your bike around your block 6 times and the whole neighborhood 5 times in 16 minutes. you can ride your bike around your block 3 times and the whole neighborhood 10 times in 23 minutes. how long does it take you to ride around the neighborhood?