Arithemetic Mean

Arithmetic Mean

 

Understanding Arithmetic Mean

For three numbers a, b and c in arithmetic progression, the middle number is called the arithmetic mean.

For example,

• 2, 5, 8 are in arithmetic progression. Their arithmetic mean is 5.
• 4, 9, 14 are in arithmetic progression. Their arithmetic mean is 9.
• a, (a + r), (a + 2r) are in arithmetic progression. Their arithmetic mean is (a + r).

Property of Arithmetic mean

Let three numbers a, b and c be in arithmetic progression. Thus,

b - a = c - b ... Statement 1

Simplifying the above expression,

2b = a + c ... Statement 2

b = (a + c)/2 ... Statement 3

The above three statements are useful in solving questions related to Arithmetic Progressions.