The average (arithmetic mean) of y numbers is x. If 30 is added to the set of numbers, then the average will be x − 5. What is t
he value of y in terms of x ?
2 answers:
Answer:
y = 
Step-by-step explanation:
Let the total numbers are n.
If the average of y numbers is x then we can form an equation

⇒ 
⇒ n =
--------(1)
Now 30 is added to the set of numbers then average becomes (x - 5)

⇒ 
⇒ (n + 1) = 
⇒ n =
- 1 ----- (2)
Now we equate the values of n from equation 1 and 2
=
- 1
y(x - 5) = x(y + 30) - x(x - 5) [ By cross multiplication ]
xy - 5y = xy + 30x - x² + 5x
xy - xy - 5y = 35x - x²
-5y = 35x - x²
x² - 35x = 5y
y = 
Answer: y = x/5 - 7
Step-by-step explanation:
Please see the workings attached .
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Answer:
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Answer:
Step-by-step explanation:
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