Question

2. Nancy is saving $2 from her allowance every week. Marco

is saving $1 the first week, $2 the second week, $3 the third
week, and so on. At the end of 10 weeks, who will have
saved more money? How much more?

Answer 1

Explanation:

Nancy just has linear savings of N=2w

Marco has the sum of an arithmetic sequence of the form M=w(w+1)/2 or (w^2+w)/2

After 10 weeks Nancy has 2(10)=$20

Marco has (100+10)/2=$55

So Marco saved 55-20=$35 more than Nancy after 10 weeks.

Answer 2

Marco will have $35 more than Nancy.

Explanation: