$394.25 would be the amount he would make if he sells all his cards
I was a little confused myself but if it is asking for the cost of the sneakers after the 20% off from the amount of money the store had to pay, it would be D, $21.84. The way to do this would be to find the cost of the sneakers when the store bought them. You multiply the percentage in decimal form with the cost of the sneakers at the price the store was selling it: 0.3*39 = 11.7. Then, to get the price the store bought them at, you would subtract that price from $39 to get $27.30. Finally, you apply the 20% discount to 27.30 by multiplying 0.2 to it and subtracting that price from 27.30. Then your answer will be $21.84. However, if the problem was asking for the cost of sneakers after the 20% off from the price the store was selling it, it would be A, $31.20. You would have to multiply the 20% discount straight to the price the store is selling the sneakers, $39. Then subtract that price from $39 to get $31.20.
S+m+l=28
4s+2m+l=58
6s+5m+4l=135
Eliminate the variable l from the first 2 equations
s+m+l=28
-4s-2m-l=-58
-3s-m=-30
Elminiate the variable l from the last 2 equations
6s+5m+4l=135
-16s-8m-4l=-232
-10s-3m=-97
Now solve for s and m using the 2 equations without l
-3s-m=-30
-10s-3m=-97
9s+3m=90
-10s-3m=-97
-s=-7
s=7
Then plug in s into one of the equations without l
-3(7)-m=-30
-21-m=-30
-m=-9
m=9
Now plus in s and m into one of the original 3 equations
(7)+(9)+l=28
16+l=28
l=12
Final answer:
Small=$7
Medium=$9
Large=$12
I know it only asks for large but I wanted to show you how to find them all for future reference. :)
Answer:
<h2>In a quadrilateral, opposite angles are congruent.</h2>
Step-by-step explanation:
Angle B & D are both opposite to each other, yet congruent.
You can see how this works by thinking through what's going on.
In the first year the population declines by 3%. So the population at the end of the first year is the starting population (1200) minus the decline: 1200 minus 3% of 1200. 3% of 1200 is the same as .03 * 1200. So the population at the end of the first year is 1200 - .03 * 1200. That can be written as 1200 * (1 - .03), or 1200 * 0.97
What about the second year? The population starts at 1200 * 0.97. It declines by 3% again. But 3% of what??? The decline is based on the population at the beginning of the year, NOT based no the original population. So the decline in the second year is 0.03 * (1200 * 0.97). And just as in the first year, the population at the end of the second year is the population at the beginning of the second year minus the decline in the second year. So that's 1200 * 0.97 - 0.03 * (1200 * 0.97), which is equal to 1200 * 0.97 (1 - 0.03) = 1200 * 0.97 * 0.97 = 1200 * 0.972.
So there's a pattern. If you worked out the third year, you'd see that the population ends up as 1200 * 0.973, and it would keep going like that.
So the population after x years is 1200 * 0.97x
