A model of a building is constructed using a scale of
1 inch : 4.5 feet. If the model is
12 inches tall, then the actual
building is feet tall.

Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e.g. 98.765).

If a line is defined by the equation y = 5x + 2, what is the slope?

Bob the builder is making 480kg of cement mix. this is made by cement, sand and gravel in the ratio 1: 3: 4