Question

Students collected recyclables for fundraising over a three-week period. Use matrix multiplication to find the total amount of money collected for each type of item.

Answer 1

gotchu so far

Answer 2

okay

Answer 3

Hmm, actually think there is a much easier method here.

Just look at one item at a time,
The glass row in the first table, and the glass column in the second.


Multiply the row vector with the column vector (a dot product)
so get a single number,
the total amount made from glass over the three week period

Answer 4

Glass total \[\begin{bmatrix}29&25&16\end{bmatrix}\begin{bmatrix}0.02\\0.02\\0.01\end{bmatrix}
=(29)(0.02)+(25)(0.02)+(16)(0.01)=\]

Answer 5

umm so i multiply all that?

Answer 6

yeah what do you get for the total sales of glass

Answer 7

1.24 i just did it

Answer 8

wait all my options start with that

Answer 9

yeah good.

Answer 10

now Cans, will be the second row of table, and the second column of table two
\[\begin{bmatrix}8&11&6\end{bmatrix}\begin{bmatrix}0.70\\0.55\\0.42\end{bmatrix}
=(8)(0.70)+(11)(0.55)+(6)(0.42)=\]

Answer 11

14.17?

Answer 12

yep.

now Newspapers
\[\begin{bmatrix}163&127&206\end{bmatrix}\begin{bmatrix}0.02\\0.01\\0.02\end{bmatrix}
=\]

Answer 13

8.65

Answer 14

yes

Answer 15

And finally, Office paper \[\begin{bmatrix}53&107&84\end{bmatrix}\begin{bmatrix}1.06\\1.00\\1.03\end{bmatrix}
=\]

Answer 16

249.70

Answer 17

Good!

Answer 18

THANK YOU