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4 votes
If the average (arithmetic mean) of 4,a,b and 6 is 7, what is the value of a+b

2 Answers

5 votes

Answer:

The sum of numbers a and b,

i.e., a + b is 18

Explanation:

Given the average (arithmetic mean) of 4, a, b, 6 is 7

Then, according to question,


((4+a+b+6))/(4) = 7

4 + a + b + 6 =
7*4

10 + a + b = 28

a + b = 28 -10

a + b = 18

Therefore, the sum of numbers a and b, i.e., a + b is 18

User Shinese
by
7.2k points
4 votes

Answer:

a+b=0.7

Explanation:

  • The average of a "n" finite serie of numbers can be calculated as
    average= (1)/(n)*(x_1+x_2+....+x_n), being
    (x_1,x_2,...x_n) the finite serie of numbers.
  • Then, applying this equation to your data, where you have
    (x_1,x_2,....,x_n)=(4,a,b,6)., means that
    7=(1)/(4) *{(4+a+b+6).
  • This yields in a+b=0.7
User John Lui
by
7.8k points