What the median 25,23,17,15,19,21,28,30,26,28 a 20 b 21 c 23 d 24 need answer fast

D

Step-by-step explanation:

the median is the middle value of a data set in ascending order

If there is not an exact middle then it is the average of the values on either side of the middle

Arrange data in ascending order

15, 17, 19, 21, 23, 25, 26, 28, 28, 30

the middle is between 23 and 25 , hence

median = = = 24

Since we know that

(a+b)

2

=a

2

+2ab+b

2

(a−b)

2

=a

2

−2ab+b

2

Now,

(i)

(x+3y)

2

=x

2

+2×x×3y+(3y)

2

=x

2

+6xy+9y

2

(ii)

(2x−5y)

2

=(2x)

2

−2×2x×5y+(5y)

2

=4x

2

−20xy+25y

2

(iii)

(a+

5a

1

)

2

=a

2

+2×a×

2a

1

+(

2a

1

)

2

=a

2

+1+

4a

2

1

(iv)

(2a−1a)=(1a)

2

(1a)

2

=1a

2

Answer