SOLUTION: The mean of 4 numbers is 5 and the mean of 3 different numbers is 12. What is the mean of the 7 numbers together? Produce an algebraic solution. Guess and check is unacceptable.

Question 929099: The mean of 4 numbers is 5 and the mean of 3 different numbers is 12. What is the mean of the 7 numbers together? Produce an algebraic solution. Guess and check is unacceptable.
Found 2 solutions by richard1234, TimothyLamb:
Answer by richard1234(7193) (Show Source): You can put this solution on YOUR website!
Sum of first 4 numbers = 4*5 = 20
Sum of other three numbers = 3*12 = 36
Sum of all seven numbers = 20+36 = 56
Mean of the seven numbers = 56/7 = 8
Answer by TimothyLamb(4379) (Show Source): You can put this solution on YOUR website!
x = sum of the four numbers
y = sum of the three numbers
---
x/4 = 5
y/3 = 12
---
x = 5*4
y = 12*3
---
x = 20
y = 36
---
(x + y)/7
(20 + 36)/7
---
answer:
8
---
Solve and graph linear equations:
https://sooeet.com/math/linear-equation-solver.php
---
Solve quadratic equations, quadratic formula:
https://sooeet.com/math/quadratic-formula-solver.php
---
Convert fractions, decimals, and percents:
https://sooeet.com/math/fraction-decimal-percent.php
---
Calculate and graph the linear regression of any data set:
https://sooeet.com/math/linear-regression.php
RELATED QUESTIONS
The geometric mean of two numbers is 4 and their harmonic mean is 3.2 find the... (answered by math_tutor2020)
the mode of 5 numbers is 1, the median is 5 and the mean is 4. what are the... (answered by Edwin McCravy)
if the mean of 12 numbers id 15, then what is the sum of the... (answered by jim_thompson5910,stanbon)
The mean of 4 numbers is x , the mean of the same 4 numbers and 73 is 9 , find... (answered by ankor@dixie-net.com)
the mean of five consecutive numbers is eleven.find the numbers (answered by Boreal)
The mean of 18 numbers is 50. If 6 of the numbers have a mean of 46, what is the mean of... (answered by ewatrrr)
The mean of 12 numbers is 18. If each of the first 6 numbers is increased by 2 and each... (answered by ankor@dixie-net.com)
A set of 9 numbers {3, 3, 4, 5, 5, 5, 6, 7, 7} has a mean of 5. Another number is added... (answered by ikleyn)
The average of 10 numbers is 6.the average of 5 numbers is 12. What is the mean of the... (answered by greenestamps)