Answer:
To increase the mean of 4 numbers by 3, the sum of the 4 numbers would have to increase by 12.
Explanation:
Here's the calculation:
Let's assume the original mean of the 4 numbers is 'x'.
To increase the mean by 3, the new mean would be x+3.
The sum of the 4 numbers after the increase would be 4(x+3) = 4x + 12.
The original sum of the 4 numbers would be 4x.
Therefore, the increase in the sum of the 4 numbers would be 4x + 12 - 4x = 12.