# Math Help - worded matrix equation

1. ## worded matrix equation

hello
three groups of children A B and C sold sweets on three consecutive days of the week. On day 1 the three groups made a profit of $20, with group A B, and C making an average profit per child of 1$ 2$and 1$ respectively. on day 2 the three respective groups made a profit per child of 3$-1$ and 2$respectively. on the whole day they made a profit of 22 on that day. on day 3 the total profit was only 7$ and profits per child were 2$1$ and -4$for the respective groups. i have come up with the following equations. are they correct? A1+B2+C= 20 A3-B+2C=22 A3+B-4C=7 am suposed to solve for the number of students in each group by expressing in echelon form then row reduce to solve.. i would like to see how its done. 2. Originally Posted by sigma1 hello three groups of children A B and C sold sweets on three consecutive days of the week. On day 1 the three groups made a profit of$20, with group A B, and C making an average profit per child of 1$2$ and 1$respectively. on day 2 the three respective groups made a profit per child of 3$ -1$and 2$ respectively. on the whole day they made a profit of 22 on that day. on day 3 the total profit was only 7$and profits per child were 2$ 1$and -4$ for the respective groups.

i have come up with the following equations. are they correct?

A1+B2+C= 20
A3-B+2C=22
A3+B-4C=7

am suposed to solve for the number of students in each group by expressing in echelon form then row reduce to solve.. i would like to see how its done.
you are solving for A,B,C from the system of matrices that you have set up.

Row reduced echelon form should be in your book. Almost every linear algebra book gives you instructions on how to work with that process.