Sequence numbers

Exercise and reference answers

Questions

1. Answer

   3

   Question

   Common difference of 1, 4, 7, 10

2. Answer

   3

   Question

   Common ratio of 1, 3, 9, 27

3. Answer

   15

   Question

   Fifth triangular number

4. Answer

   55

   Question

   Sum of the first 10 natural numbers

Instructions

Type the number only.

Explanation