4 boys have a mean height of 162cm. Another boy with a height of 165cm joins them. What is the new mean height?

162.6cm

Step-by-step explanation:

4 boys have a mean height of 162cm. Their total height will be the average multiplied by the number of boys which will be:

= 162 × 4

= 648cm

A new boy with height of 165cm joined. This means that we now have 5 boys and their total height will be:

= 648cm + 165cm

= 813cm

The new mean height will be:

= Total height / Number of boys

= 813 / 5

= 162.6cm

3x + 18 = 147°

step-by-step explanation:

3x + 18 = 147°, because the value of the central angle is equal to the value of the arc formed by it.

i hope i you.

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)