Answer:
2.5 years
Step-by-step explanation:
Interest= P×R×T÷100
T= 100I÷P×R
T= 100×400÷8000×2
T= 40000÷16000
T= 5÷2
T= 2.5 years
Since both values are positive, it is in quadrant 1
We know that the profit from an item is the sale price minus the cost price. Thus,
1269 - 0.2x² - 830 - 398x
P(x) = -0.2x² - 398x + 439
Local maxima are located at the points where the first derivative of a function are 0
P'(x) = -0.4x - 398
398 = -0.4x
x = -995
There is only one maximum so the average value is -995
A=x+y+z/3
a-x=y+z/3
a-x-z/3=y
so y=a-x-z/3
