Karen has used 12 feet of ribbon for a project. this represents 3/8 of the total amount of ribbon. how much ribbon did she have at the start of her project?

In the surface area formula for cylinders which expressionrepresents the lateral area

What is the length of the unknown leg in the right triangle ?

Abox contains 1 plain pencil and 4 pens. a second box contains 5 color pencils and 5 crayons. one item from each box is chosen at random. what is the probability that a plain pencil from the first box and a color pencil from the second box are selected? write your answer as a fraction in simplest form.