Add y to both sides then do the algebra
Answer:
The new mean for the exam scores is 51
Step-by-step explanation:
the mean can be calculated using the formula
mean of scores = 
before the 20 points was added, the mean of the score was = 50.
Inserting this into the formula, we have:
50 = 
from this, we can compute the sum total of the scores as
sum total = 50 × 20 = 1000
when the extra 20 marks is added, the sum of the entire scores will be changed to 1000 + 20 = 1020.
Hence the new mean will be computed as (New Sum total of scores / Number of students)
=
= 51.
∴ The new mean of the scores is = 51
Answer:
81a^2+16b^2
Step-by-step explanation:
When we do this, the base of the parallelogram has length b 1 + b 2, and the height is the same as the trapezoids, so the area of the parallelogram is (b 1 + b 2)*h. Since the two trapezoids of the same size created this parallelogram, the area of one of those trapezoids is one half the area of the parallelogram