James is trying to save money for college. When
he is 5 years old, his uncle puts $750 into a
savings account for him. The money should
increase by 5% each year until he needs it for
college.
Write an exponential model for this situation.

Respuesta :

Answer:

[tex]y=(750)1.05^t[/tex], where [tex]t[/tex] is the time (in years) from investment

Or  [tex]y=(750)1.05^{t-5}[/tex], where [tex]t[/tex] is the age of James

Step-by-step explanation:

exponential model:  [tex]y=ab^t[/tex],  where [tex]t[/tex] is the time (in years) from investment

when t = 0, y = 750

[tex]\implies 750=ab^0[/tex]

As [tex]b^0=1[/tex]

[tex]\implies 750=a[/tex]

Therefore, [tex]y=750b^t[/tex]

If the savings increase by 5% each year, then b = 105%.

105% = 105/100 = 1.05

Therefore, b = 1.05

So final model: [tex]y=(750)1.05^t[/tex], where [tex]t[/tex] is the time (in years) from investment

Or, we can write this as [tex]y=(750)1.05^{t-5}[/tex], where [tex]t[/tex] is the age of James