There are 20 students in a drama class. The mean age of 12 students is 18 years. The mean age of the remaining 8 students of the drama class is 23 years. What is the mean age of all the students in the drama class?

Step-by-step explanation:

Total sum of age of 12 students = 12*18 = 216;

Total sum of age of 8 students = 8*23 = 184;

Total sum of age of 20 students = 216+184 = 400;

Mean age of all the students = total age / number of students;

= 400/20 = 20 year

Step-by-step explanation:

sas (side angle side)

aa (angle angle)

sss(side side side)

sas find two sides with an angle in between

aa is finding two angles and the third will add up to 180

sss find all sides

step-by-step explanation:

system of linear equation

step-by-step explanation:

as given in the data

a= 20 , b= -12

let us suppose that it is a straight line equation

now we know the formula for the system of linear equation

b= ma + c )

here m is slope of a straight line which is equal to formula

m=   (ii)

and here c is a constant

now putting the value of a and b in equation (ii)

m=

m=

putting the value of a,b and m in equation (i) gives us

-12 = + c

-12=-12 + c

adding 12 to both sides

-12 +12 = -12 +12 +c

0 =c

or c=0

as the value of the constant is zero which gives us that it is a linear equation and this order pair satisfies the system of linear equations.