Andria has only nickles and pennies. There are 12 nickles and 8 pennies. What is the ratio of nickles to total coins in her purse. 12 : 8 8 : 12 12 : 20 20 : 12

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Suppose that one doll house uses the 1 inch scale, meaning that 1 inch on the doll house corresponds to 1/2 foot for life-sized objects. if the doll house is 108 inches wide, what is the width of the full-sized house that it's modeled after? in inches and feet.

Find the domain of the following expression: 1/(√x)-2