Question

Mean of first ten odd multiples of seven

Answer 1

First 10 odd multiples of 7 are

7, 21, 35, 49, 63, 77, 91, 105, 119, 133

$Mean \\ = \frac{7 + 21 + 35 + 49 + 63 + 77 + 91 + 105 + 119 + 133}{10} \\ = \frac{700}{10} = 70$

Answer 2

Answer:

Mean = 70

Step-by-step explanation:

Mean of first ten odd multiples of seven

First Ten odd multiples of 7 are

 7 * 1  , 7 * 3 , 7 * 5 ,  7*7  , 7*9 , 7*11 , 7*13 , 7*15 , 7*17 , 7*19

Sum of all these

= 7(1 + 3 + 5 + ................................+17 + 19)

1 + 3 + 5 + ................................+17 + 19 are in AP

a = 1  n = 10 Last term = 19

Sum of n terms = (n/2)(first Term + Last Term)

= (10/2)(1 + 19)

= 100

Sum of First Ten odd multiples of 7 = 7*100 = 700

Terms = 10

Mean = Sum/Numer of terms

=> Mean = 700/10

=> Mean = 70

Mean of first ten odd multiples of seven = 70