The formula to use is
A = P*(1+r/n)^(n*t)
where P, r and t are fixed values given as such
Note how I'm using the decimal form of 6%. If we let n vary, then we're basically making this the x value. So replace n with x. Let A = f(x)
Doing all these substitutions has
A = P*(1+r/n)^(n*t)
transform into
f(x) = 10900*(1+0.06/x)^(x*9)
which can be typed into desmos as you can see in the attached screenshot image below
Then on the next line, you can input f(1) to find the y output value when x = 1. This is the same as finding the value of A when n = 1. In other words, this finds out how much money you get after compounding annually (or 1 time per year). Repeat for...
The continuous compounding will need another formula. That formula is
A = P*e^(r*t)
The A, P, r and t are the same from before. The new addition is the 'e'. This is a special constant much like pi = 3.14 is. In this case, e = 2.718 approximately. This number 'e' shows up in a lot of math problems.
We have been given the equation
It represents the number of people standing to catch a commuter train x hours after 5 A.M.
Now, in order to find the number of people in line at 7 a.m. , we need to substitute x= 2 in the above equation.
Therefore, the number of people in the line at 7 a.m. is 40
D id the correct option.