Respuesta :

Answer:

32,767 pennies

Explanation:

The number of pennies saved by Joe for the first four days forms the sequence below:

[tex]1,2,4,8\cdots[/tex]

We want to determine the total size of Joe's collection on the 15th day.

The sequence above forms a geometric sequence in which:

• The first term, a1 = 1

,

• The common ratio, r = 2/1=4/2=2

The sum of a geometric sequence is determined using the formula:

[tex]S_n=\frac{a_1(r^n-1)}{r-1},r>1[/tex]

On the 15th day: n=15

[tex]\begin{gathered} S_{15}=\frac{1(2^{15}-1)}{2-1} \\ =2^{15}-1 \\ =32768-1 \\ =32767 \end{gathered}[/tex]

If Joe continues with this pattern, he will have 32,767 pennies on the 15th day.