By normal curve symmetry
<span>from normal table </span>
<span>we have z = 1.15 , z = -1.15 </span>
<span>z = (x - mean) / sigma </span>
<span>1.15 = (x - 150) / 25 </span>
<span>x = 178.75 </span>
<span>z = (x - mean) / sigma </span>
<span>-1.15 = (x - 150) / 25 </span>
<span>x = 121.25 </span>
<span>interval is (121.25 , 178.75) </span>
<span>Pr((121.25-150)/25 < x < (178.75-150)/25) </span>
<span>is about 75%</span>
Are you looking for the amount after interest gained? If so I believe the answer would be $40.
500 x 0.04 x 2 = 40
Answer: y= (-1/5)x -4
First move the x over t the other side of the equation. Now we have 5y=-x-20. Next divide everything by 5 to get y= (-1/5)x -4
