Average (mean) = (sum of all the data) / (# of data)
sum of all the data = (average)(# of data)
Thus for 100 students with an average of 93,
sum of all data = (93)(100) = 9300
and for 300 students with an average of 75,
sum of all data = (75)(300) = 22500
Therefore you would expect the overall average to be
(9300 + 22500) / (100 + 300) = 79.5 %
Now if there are x # of advanced students and y # of regular students, then
x + y = 90 (total # of students) and 93x + 75y = 87(x + y) (overall average)
The second equation can be simplified to x - 2y = 0
Subtracting the two equations yields
x = 60 and y = 90
Therefore you would need 60 advanced and 30 regular students.
Answer:
the answer is -1 1/5
Step-by-step explanation: 7/5
Answer:
30 yrs
Step-by-step explanation:
SI = PRT/100
T = I × 100/PR
= 9000×100/1500×20
= 900000/30000
= 30 yrs
Answer:
Commutative
Step-by-step explanation:
There are four basic property of operations to solve an algebraic expressions. They are associative, commutative, distributive and identity.
The expression given is : 
So the given algebraic expression is a commutative property of operations. The commutative property states that when any two numbers are added in an expression the sum of the numbers are the same regardless of the order of the numbers that are added.
Thus the sum of the above expression will be same in which ever order the numbers are added.
