Answer:
Sum : 65
Explanation:
In this notation, n is our starting value, and hence we start at 3 and go to 7. Given the set of values : { 3, 4, 5, 6, 7 }, we can substitute in our expression " 4n - 7 " for n and solve. The sum of these values is our solution.
4( 3 ) - 7 = 12 - 7 = 5,
4( 4 ) - 7 = 16 - 7 = 9,
4( 5 ) - 7 = 20 - 7 = 13,
Our remaining values for n = 6 and n = 7 must then be 17 and 21. This is predictable as we have an arithmetic series here, the common difference being 4. As you can see 9 - 5 = 4, 13 - 9 = 4, 17 - 13 = 4, 21 - 17 = 4.
Therefore we have the series { 5, 9, 13, 17, 21 }. This adds to an answer of 65.