Answer:
which statements is there meant to be a diagram? ?
So, since averages are defined as:

So, since P are the total number of elements and P_k is the P_kth student. This is saying if we sum over each student's score and divide it by the number of students, we should get P, which is true.
So, using that logic, the other class can be represented as:

We can take both of these equations and multiply them by N:


So, if we want to find the average of this we should add both our equations then divide by P+N, which is the number of all the students.

To make this simpler we can replace our LHS with 86, since that's the average of both classes combined.

Simplified we would have P/N=3/8.
Answer:
Amount of money paid by each student is equal to 
Step-by-step explanation:
Given: A group of children bought
presents that cost
each and a card that cost
.
To find: amount of money each student paid in terms of 
Solution:
Cost of each present 
Cost of
presents 
Cost of a card 
Therefore,
Amount of money paid by each student in terms of
= Cost of
presents + Cost of a card

Answer: 6(u-2)+2=6u-10
Step-by-step explanation:
Then, any value of u makes the equation true.
Answer:
it is x=7
x=-1
Step-by-step explanation:
i using the quadratic formula