Explain 40 x 50 using mental math

Simplify 8m+4n+7m-2n

Find the difference: square root20 - square root80

Solve for y. 3 (y + - 11.8) + 11.48 = - 7.42 y =

What is 5 times 25 divided by the square root of 225 subtracted from 10,247 and than added to pie.

Which runner came first 8.016 7.049 7.03 or 8.16?

A librarian has weekend off and has 10 paid vacation days per year

A country's population in 1990 was 132 million. In 1998 it was 137 million. Estimate the population in 2003 using the exponential growth formula. Round your answer to the nearest million.

Simplify 7x + 2y - 3x - 5y

The staircase has treads that are 10 inches deep with 7 inch high risers. If the staircase needs to reach a total height of 8 feet, 2 inches. How much floor space needs to be allowed for the staircase?

During one month of cell phone use, Noah used 200 anytime minutes and 400 text messages, and paid $80. the next month, he used 150 anytime minutes and 350 text messages, and paid $67.50.