Question 7: A small business has a choice of investing $20 000 in one of two projects. The revenue flows from the two projects during the next 4 years are listed in the following table. (20) Revenue($)
End of year
Project A
Project B
1
6 000
10 000
2
3 000
6 000
3
10 000
9 000
4
8 000
1 000
Total
27 000
26 000
● If the interest rate is 11% compounded annually, which of these two projects would you advise the company to invest in?
4x+2y=2
5x+2y-4x-2y=0-2
x=-2
y=5
2) х+5у=7 3х+2у=-5
3x+15y=21
3x+15y-3x-2y=21+5
13y=26
y=2
x=-3
3) 2х-3у=1 3х+у=7
9x+3y=21
2x-3y+9x+3y=1+21
11x=22
x=2
y=1
4) х+у=6 5х-2у=9
2x+2y=12
2x+2y+5x-2y=12+9
7x=21
x=3
y=3
5) х+у=7 5х-7у=11
5x+5y=35
5x+5y-5x+7y=35-11
12y=24
y=2
x=5
6)4х-3у=-1 х-5у=4
4x-20y=16
4x-20y-4x+3y=16+1
-17y=17
y=-1
x=-1
7)2х-5у=-7 х-3у=-5
2x-6y=-10
2x-6y-2x+5y=-10+7
-y=-3
y=3
x=4
8)3х-5у=16 2х+у=2
10x+5y=10
3x-5y+10x+5y=16+10
13x=26
x=2
y=-2
9) 2х+5у=-7 3х-у=15
15x-5y=75
2x+5y+15x-5y=75-7
17x=68
x=4
y=-3
10) 2х-3у=5 х-6у=-2
2x-12y=-4
2x-3y-2x+12y=5+4
9y=9
y=1
x=4