Question

Sue set up a lemonade stand and sold 10 glasses of lemonade in the first hour. Her sales increased at the rate of 20% per hour for the next n hours. Which function represents the total number of glasses she sold in the nth hour? If the price of 1 glass of lemonade is $0.50, how much money did she earn in the nth hour? The function that gives the total number of glasses sold in the nth hour is , and the money she earned in the nth hour is .

Answer 1

This is compound interest
$A=P(r+1)^t$
r=rate
P=original amount
t=time in hours
$A=10(0.2+1)^t$

$A=10(1.2)^n$ is the number of glasses in n hours
price=cost time number of glasses
0.5 times $10(1.2)^n$ is $5(1.2)^n$



total glasses sold in n hours is
$f(n)=10(1.2)^n$
the function for money eraned in the nth hour is
$f(n)=5(1.2)^n$