Average of 5 numbers is 16 and four of the numbers are 12 14 16 and 18. find the fourth number

Given:

average of five numbers is 16 and four of the number are 12 , 14, 16 and 18

To find:

the remaining number

Solution:

The given numbers are 12,14,16,18

Let the another number be X

Sum of five numbers = 12+14+16+18+X

=60+X

Average of five numbers =16

Average= Sum of observations/no.of

observations

=>16=(60+X)/5

=>(60+X)/5=16

=>60+X=5×16

=>60+X=80

=>X=80-60

=>X=20

The fifth number is 20

20

Step-by-step explanation:

let the number be x

Average=sum/number

16 = x+12+14+16+18/5

16=x+60/5

16×5 =x+60

80=x+60

80-60=x

x=20

✓ the fifth number is 20.

hope it helps.

answer: 204

step-by-step explanation:

we are told that the revenue is

x⋅(4080−10x)=−10x^2+4080x

this is a quadratic function, so to maximize it we should find the x-value of its vertex. recall that the x-value of the vertex of the parabola ax^2+bx+c is given by the formula −b/2a.

so in this case, we have a=−10 and b=4080, so the x-value of the vertex is

−b/2a= −(4080)/2(−10)=204