Problema Solution

Mary has an antique marble collection containing 40 marbles. She has five more red marbles than blue and twice as many red as green marbles. Write a system of equations to find the number of each color of marble.

Answer provided by our tutors

We will assume that Mary has red, blue and green marbles only.

Let

x = the number of red marbles

y = the number of blue marbles

z = the number of green marbles

x + y + z = 40

x = y + 5

x = 2z

........

click here to see the system of equations solved for x, y and z

........

x = 18 red marbles

y = 13 blue marbles

z = 9 green marbles

Mary has 18 red, 13 blue and 9 green marbles.