SOLUTION: Good Afternoon, I need help understanding how to work algebra word problems. 1) $5400 is invested, part of it at 11% and part of it at 6%. For a certain year, the total yield

Algebra ->  Equations -> SOLUTION: Good Afternoon, I need help understanding how to work algebra word problems. 1) $5400 is invested, part of it at 11% and part of it at 6%. For a certain year, the total yield      Log On


   

Question 1011344: Good Afternoon,
I need help understanding how to work algebra word problems.
1) $5400 is invested, part of it at 11% and part of it at 6%. For a certain year, the total yield is $474.00. How much was invested at each rate?
2) One day a store sold 19 sweatshirts. White ones cost $10.95 and yellow ones cost $12.50. In all $229.75 worth of sweatshirts were sold. How many of each color were sold?
Thanking you in advance
Betty
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
The two questions are similar, but here is just #2.

w white ones and y yellow ones;
system%28w%2By=19%2C10.95w%2B12.5y=229.75%29

The money equation both members divided by 0.05,
219w%2B250y=4595

Use substitution with y=19-w;
219w%2B250%2819-w%29=4595
219w%2B4750-250w=4595
219w-250w=4595-4750
-31w=-155
w=155%2F31
highlight%28w=5%29
-
highlight%28y=14%29




Here is how you can start #1:
x at the lower rate, 5400-x at the higher rate;
%2811%2A%285400-x%29%2B6%2Ax%29%2F100=474, to use just one variable instead of two variables.