Question

If you save three pennies on January 1, six pennies on January 2, nine pennies on January 3, and continue this pattern for one year (not a leap year), what will be the value of your entire savings, in dollars, at the end of that one year? Express your answer as a decimal.

Answer 1

its just increasing by 3 pennies each day

Answer 2

so on jan 4th you will have 12 pennies and so on

Answer 3

ok can you please explain and show how [:

Answer 4

how many pennies do you think he will have on jan 5th?

Answer 5

and do you have choices for answers?

Answer 6

let n is the order of the day, \(a_n\) is the money you save on that day
n=1 \(a_1=3\)
n =2 \(a_2= 6 = a_1*2\)
n = 3 \(a_3 =9 = a_1*3\)
n = 4 \(a_4 = 12 = a_1 *4\)
----and----so----on-------------
so, if n = 365 \(a_{365}= a_1* 365\)
therefore, \(a_1 +a_2+a_3+.....+a_{365} \) is the total money you can save for the whole year
And you have formula \(\sum_ {n=1}^{365} 3n\)
and how to calculate this sum? You google to know, I explain you the way how to construct that formula. That's it.