| 1. Use
the definition of Averages
|
2. Express
it as a sum of the numbers
a + b + c + d = 4 average |
| 3. Use the additional information you are given | |
Working with Averages Up
| 1. Use
the definition of Averages
|
2. Express
it as a sum of the numbers
a + b + c + d = 4 average |
| 3. Use the additional information you are given | |
Sample 1
The
average of 4 numbers is greater than 7 and less than 11.
What is one possible
number that could be the sum of these 4 numbers ?
Let a, b, c, d the given numbers
Step 1
Use
the definition and write the combined Inequality:
Step 2
Express it as a sum of 4
numbers:
28 < a + b + c + d < 44
Step 3
Pick
out any number between 28 and 44. Possible answer is 30.
Sample 2
If
the average of a, b and c is 10, and the average of a, b and 2c is 14,
what is the average of a
and b ?
Step 1
Use the definition for the first part of info given
Step 2
Express it as a sum of a, b, c
a + b + c = 30
Step 3
Use the definition of average for the second part of problem
Step 4
Express it as a sum of a, b, c, c
a + b + c + c = 56
Step 5
Substitute a + b + c = 30 in Step 4
30 + c = 56
Step 6
Solve for c
c = 26
Step 7
Find a + b using a + b + c = 30 and substitute 26 for c
a + b + 26 =
30
a + b = 4
Step 8
Find average of a and b
Answer
is 2
Up
