Can you explain a "true proportion"?

Charlie's eraser has a mass of 9 grams. How many milligrams is the eraser?

The area of the square above is 400. What is the value of t?

A 20 foot ladder is leaning against the side of a building. The bottom of the ladder is 4 feet from the wall. How many feet above the ground does the ladder touch the wall?

Mary wrote the number 2.3 x 103 in standard form. Which number did she write?

An architectural drawing lists the scale as 1/4" = 1'. If a bedroom measures / (6/frac34/) " by / (4/frac12/) " on the drawing, how large is the bedroom?

Suppose you are getting new inground pool at your house. The pool is going to be a rectangle that is 30 feet by 15 feet. The outside border of the deck around the pool will also be a rectangle, which is 44 feet by 28 feet.

There are 12 team members. They each ate 3 slices of pizza. Each pizza was cut into 8 slices. What fraction of the pizza did the team eat altogether?

Solve for v 12v = 18+6v

Maggie's brother is four years younger than twice her age the sum of their ages 11 how old is Maggie?

Kirsten invested $1000 in an account at an annual interest rate of 3%. She made no deposits or withdrawals on the account for 5 years. The interest was compounded annually. Find the balance in the account, to the nearest cent, at the end of 5 years.