Question

Среднее арифметическое двух чисел равно 9. Одно из этих чисел равно 6,5 .Найдите второе число.

Answer 1

Среднее арифметическое - 9
1 число - 6,5
2 число - х
(х + 6,5) : 2 = 9
х + 6,5 = 9 * 2
х + 6,5 = 18
х = 18 - 6,5
х = 11,5 - 1 число
Ответ: 11,5

Answer 2

To find the second number, we can use the formula for the arithmetic mean (average):

Arithmetic Mean = (Sum of numbers) / (Number of numbers)

In this case, the arithmetic mean of two numbers is 9, and one of the numbers is 6.5. Let's represent the second number as "x".

So, the equation will be:

(6.5 + x) / 2 = 9

To solve for "x", we can first multiply both sides of the equation by 2:

6.5 + x = 18

Now, isolate "x" on one side by subtracting 6.5 from both sides:

x = 18 - 6.5

x = 11.5

Therefore, the second number is 11.5.