A store sells televisions for $360 and video cassette recorders for $270. at the beginning of the week its entire stock is worth $45,990. During the week it sells three quarters of the televisions and one third of the video cassette recorders for a total of $27,630. How many televisions and video cassette recorders did it have in its stock at the beginning of the week?

Question

drwls · Accepted Answer

You need to write two equations in two unknowns, and then solve for them both.
Let x be the original number of TVs and y be the original number of VCRs.

Here is what you know:
360 x + 270 y = 45,990
(3/4)*360 x + (1/3)*270 y = 27,630
which can be simplified to:
270 x + 90 y = 27,630

Tripe the last equation and subtract the first.

810 x + 270 y = 82,890
360 x + 270 y = 45,990
______________________
450 x = 36,900
x = 820

Use any of the original equations to solve for y.

Lena · Answer

I've been working on this for a while but I cant seem to get anywhere with this. I created this equation.

360(x) + 270 (y) = $ 45,990
360 (3x/4) + 270 (x/3) $27, 630

There's a starting point. If I figure out how to solve this I'll post.