Answer: P(mean x<18.1077) = P(z< -2.67) = 0.0038
Step-by-step explanation:
Value of Z for 18.1077 = (18.1077 - 19.5)/0.5209 = -2.67
First account: $6500
Second account: $8500
Set x is amount of money in first account
=> x + 2000 is money in second account.
X*3% + (x+2000)*4% = 535
=> x = (53500 - 8000) / 7
X = 45500 / 7 = 6500
=> account #1 = x = 6500
Acc #2 = x + 2000 = 6500 + 2000 = 8500
An= A1 r ^(n-1)
An= -4 (-3)^(n-1)
An= -4 (-3)^(7-1)
An= -4 (729)
An= -2916
I think this is right :)
Y represent the total number of newspapers sold by Colby.
