Four friends agree to save money for a graduation road trip. They decide that each of them will put $0.25 in the fund on the first day of May, $0.50 on the second day, $0.75 on the third day, and so on. At the end of May, there will be $_____ in their fund. (Hint: There are 31 days in May.)

Question

anonymous · Answer

how much do you know about summations?

anonymous · Answer

Arithmetic series.

anonymous · Answer

If im correct i think the equation should be :
Sn=(n/2)(a1+n)
multiply the sum by four

anonymous · Answer

would that equation be right?

anonymous · Answer

the easiest way (at least for me) is to represent it as $$4 \sum_{n=1}^{31} \frac{ n }{ 4 }$$

anonymous · Answer

which simplifies to $$\sum_{n=1}^{31} n$$

anonymous · Answer

wait that seems complicated -.-

mathstudent55 · Answer

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