Evaluate 15/r-1 when r=5

One pipe can empty a tank in 45 minutes while a second pipe can empty it in 60 minutes. If both pipes are opened at the same time, how long will it take to drain the tank?

What is the surface area of a cylinder that has a diameter of 10 feet and a height of 8 feet

Swati is substituting t=5 and t=9 to determine if the two expressions are equivalent.

1) At a concert, there are 3 times as many women as men. 3/5 of the men and 1/3 of the women wear glasses. There are 120 more women wearing glasses than men wearing glasses. How many people are at the concert.

If f (x) = 2x+1 and g (x) = x^-7, find (f-g) (3)

1 Find the volume of a cube of edge 8 cm. 2 Find the volume of a rectangular prism 6 cm x 9 cm x 3 cm. 3 Find the volume of a triangular prism with base area 30 cm? and height 10 cm. 4 How many litres in 5000 mL? 5 The volume of a cube is 1331 cm'.

The ages of Edna, Ellie and Elsa are consecutive integers. The Sum of their ages is 111. What are their ages?

Solve for x x-7/7 = 8/2 a) x = 63 b) x = 35 c) x = 9 2/7 d) x = 31 1/2

What is the value of x in the equation 4/9x-5=31

If 190 miles is represented on a map by 3 centimeters, what distance does 10 centimeters represent?