Mazie counted 40 black cars, 20 silver cars and 30 black cars in the parking lot. What is the ratio of white cars to the other cars in simplest forms

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Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?

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?