Skip to main content

average formula

To find the average, first we need to calculate the sum of the elements, then we have to divide the sum of the elements by the no of elements to get the average.
                                               Average= sum of elements/ no of elements

               Ex:         The average of first 5 natural numbers
                                 sum of 5 natural numbers=1+2+3+4+5=15
                                 no of elements = 5
                                 average = 15/5 =3
                                       

Comments

Popular posts from this blog

how many times a day do the minute and hour hands of a clock form a straight line but in opposite direction

For this I am not writing any formula , simply  with the help of table we will try to understand the concept. the minute and hour hands of a clock form a straight line but in opposite direction 1 Between 12.30 to 12.35 2 Between 1.35 to 1.40 3 Between 2.40 to 2.45 4 Between 3.45 to 3.50 5 Between 4.50 to 4.55 6 Between 5.55 to 6.00  : means at 6.00 clock they are straight but opposite @ Between 6.00 to 6.05 hands are not straight in opposite direction 7  Between 7.05 to 7.10 8 Between  8.10 to 8.15 9 Between  9.15 to 9.20 10 Between  10.20 to 10.25 11 Between  11.25  to 11.30                  #  goto step 1 @ in 6 th column if we see in 5 to 6 hours and 6.00 to 7.00 hours t...

Average of first n even numbers

Even numbers are 2,4,6,8,10,…. Average = sum of elements/ no of elments Now we will see the sum of elements: Sum of first 2 even numbers: 2+4= 6= 2(2+1) Sum of first 3 even numbers: 2+4+6= 12= 3(3+1) Sum of first 4 even  numbers: 2+4+6+8=20= 4(4+1) Sum of first 5 even numbers: 2+4+6+8+10 = 30 = 5(5+1) Sum of first n even numbers: 2+4+6+8+10+. . . . .  n numbers= n(n+1) Now we will see average: Average of first 2 even numbers= (2+4)/2                                                           = 6/2                              ...

sum of even numbers from 2 to 100

Even numbers from 2 to 100 Even numbers are 2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,32,34,36,38,40,42,44,46,48,50,52,    54, 56,58,60,62,64,66,68,70,72,74,76,78,80,82,84,86,88,90,92,94,96,98,100. Now we will see the sum of elements: Sum of first 2 even numbers: 2+4= 6 The above can be written as Sum of first 2 even numbers: 2+4= 6= 2x3=2(2+1) Sum of first 3 even numbers: 2+4+6= 12= 3(3+1) Sum of first 4 even  numbers: 2+4+6+8=20= 4(4+1) Sum of first 5 even numbers: 2+4+6+8+10 = 30 = 5(5+1) Sum of first n even numbers: 2+4+6+8+10+. . . . .  n numbers= n(n+1) Sum of  even numbers from 2 to 100 = 2+4+6+8+10+. . . . .  50 numbers                                                                           = 50(50+1)           ...