Question

Graham received 1 penny on the first day of the month, and each day after that he received triple the number of pennies that he received the day before. On what day of the month did Graham first receive over 3 million dollars on a single day?

Answer 1

Answer:The 19th day (Apex)

Explanation:

Answer 2

Explanation:

Graham received i penny on the first day of the month, and each day after that he received triple the number of pennies.

The sequence formed for each day pennies received will be

1, 3, 3², 3³................... n terms

Since explicit formula of a geometric series is represented by

`T_(n)=a(r)^(n-1)`

Here a = first term of the sequence = 1

r = common ratio of the sequence = 3

Now we have to calculate on which day Graham will receive 3 million dollar

So we have to find the nth term of this sequence which is equal to $3000000

Now we put these values in the explicit formula

`3000000=1.(3)^(n-1)`

Taking log on both the sides

log(3000000) =
`log(3)^(n-1)`

6.4771 = (n - 1)log3

6.4771 = (n - 1)(0.4771)

(n -1) =
`(6.4771)/(0.4771)=13.57`

n = 13.57 + 1

n = 14.57

Therefore, on 15 the day he will get over 3 million dollars.