Answer:
[tex]a_{16} = 65536[/tex]
[tex]a_{20} = 1048576[/tex]
Step-by-step explanation:
On the first day the number of people who bought the tickets is 4.
This represents the first term of a sequence.
[tex]a_1=4[/tex]
Twice as much people bought tickets on the second day,and each day after that,twice as many people bought tickets.
This means the sequence is geometric with common ratio:
[tex]r = 2[/tex]
The expresion for the 16th day is:
[tex]a_{16} = a_{1} {2}^{15} [/tex]
[tex]a_{16} = 2 \times {2}^{15} [/tex]
[tex]a_{16} = 65536[/tex]
The expresion for the 20th day is
[tex]a_{20} = a_{1} {2}^{19} [/tex]
[tex]a_{20} =2 \times {2}^{19} [/tex]
[tex]a_{20} = 1048576[/tex]
