### Theory

 1 Introduction to special series 2 Sum of first 'n' natural numbers 3 Sum of first 'n' odd natural numbers 4 Sum of squares of first 'n' natural numbers 5 Sum of cubes of first 'n' natural numbers

### Exercises

 1 Find the sum of the numbers Difficulty: easy 3 2 Determine the sum of the numbers Difficulty: easy 3 3 Find the value of the expression Difficulty: medium 4 4 Sum of the natural numbers Difficulty: medium 4 5 Find the sum of the square of natural numbers Difficulty: medium 4 6 Find the value of 'n' Difficulty: medium 4 7 Sum of cube of natural numbers up to 'k' terms Difficulty: medium 4 8 Find the average of the first 'n' natural numbers Difficulty: medium 4 9 Calculate the number of terms needed to get the sum Difficulty: hard 5 10 Find the amount of savings Difficulty: hard 5 11 Determine the value of 'n' Difficulty: hard 5 12 Find the area can be decorated Difficulty: hard 5

### Tests

 1 Training test I Difficulty: medium 11 2 Training test II Difficulty: medium 11

### Teacher manual

 1 Methodical recommendation