Question

Pippa thinks of a number. She adds 1 to it to get a second number. She then adds 2 to the second number to get a third number, adds 3 to the third to get a fourth, and finally adds 4 to the fourth to get a fifth number. If n is the number she started with, what is the sum of her numbers?

Answer 1

Answer: n + 10

Explanation:

Initial number = n

She adds 1 to it to get a second number. Second number = n + 1

She then adds 2 to the second number to get a third number. Third number = n + 1 + 2 = n + 3

She adds 3 to the third to get a fourth. Fourth number will be:

= n + 3 + 3

= n + 6

She adds 4 to the fourth to get a fifth number. Fifth number will be:

= n + 6 + 4

= n + 10