The mean of 15 numbers is 25. If each number is multiplied by 4, mean ...
We have So, Mean =
So Mean =
=25
If 4 is multiplied by each observation
So Mean =
Taking common 4 from numerator=4
=4*25=100
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The mean of 15 numbers is 25. If each number is multiplied by 4, mean ...
To find the answer simply multiply the mean by the given no. i.e. 4 explanation let sum of all 15 no. is x let new sum = 4x mean = x / 15 = 25 new mean= 4x/15 4(x/15) 4(25) answer=100
The mean of 15 numbers is 25. If each number is multiplied by 4, mean ...
Given:
- Mean of 15 numbers = 25
To find:
- Mean of the new numbers after multiplying each number by 4
Solution:
To find the mean of a set of numbers, we sum up all the numbers and divide the sum by the total count of numbers.
Step 1: Finding the sum of the original 15 numbers.
- Mean = Sum of numbers / Total count of numbers
- 25 = Sum of numbers / 15
Step 2: Finding the sum of the new numbers after multiplying each number by 4.
- Let's assume the original numbers are represented by x1, x2, x3, ..., x15.
- The new numbers after multiplying each number by 4 will be 4x1, 4x2, 4x3, ..., 4x15.
- Sum of the new numbers = 4x1 + 4x2 + 4x3 + ... + 4x15
- Since 4 is a constant factor, it can be taken out of the sum: 4(x1 + x2 + x3 + ... + x15)
- The sum of the original numbers is equal to the sum of the new numbers divided by 4.
- Sum of the original numbers = Sum of the new numbers / 4
Step 3: Finding the mean of the new numbers.
- Mean of the new numbers = Sum of the new numbers / Total count of numbers
- Mean of the new numbers = (Sum of the original numbers) / (Total count of numbers)
- Mean of the new numbers = (Sum of the new numbers / 4) / (Total count of numbers)
- Mean of the new numbers = (Sum of the new numbers) / (4 * Total count of numbers)
- Mean of the new numbers = (Sum of the new numbers) / (4 * 15)
From Step 2, we know that the sum of the new numbers is equal to the sum of the original numbers multiplied by 4.
Sum of the new numbers = (Sum of the original numbers) * 4
Sum of the new numbers = 25 * 4 = 100
Mean of the new numbers = (Sum of the new numbers) / (4 * 15)
Mean of the new numbers = 100 / (4 * 15)
Mean of the new numbers = 100 / 60
Mean of the new numbers = 5/3
Since the mean of the new numbers is 5/3, none of the given options (A, B, C, D) match the correct answer. Therefore, there seems to be an error in the question or options provided.
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