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

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 =

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

x =±sqrt(1/3)

step-by-step explanation:

x+4/6x=1/x

multiply each side by 6x to get rid of the fractions

6x*(x+4/6x)=1/x*6x

distribute

6x^2 +4 = 6

subtract 4 from each side

6x^2 +4-4 = 6-4

6x^2 =2

divide by 6

6x^2/6 = 2/6

x^2 = 1/3

take the square root of each side

sqrt(x^2) = ±sqrt(1/3)

x =±sqrt(1/3)