How many times is a group of 20 coins than a group of 5 coins

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

1. how do you convert the repeating, nonterminating decimal 0. to a fraction? explain the process as you solve the problem.

The area of a circle is equal to 1 dm². find the radius of the circle.