The average of six numbers is 48. If the average of first four is 28 and that of last three is 41, the fourth number is: Options : 47 51 49 none of these

To solve this problem, we need to use the formula for the average, which is the sum of the numbers divided by the quantity of numbers.

1. The average of six numbers is 48, so the sum of these six numbers is 48 * 6 = 288.
2. The average of the first four numbers is 28, so the sum of these four numbers is 28 * 4 = 112.
3. The average of the last three numbers is 41, so the sum of these three numbers is 41 * 3 = 123.
4. The fourth number is included in both the first four numbers and the last three numbers. So, to find the fourth number, we subtract the sum of the first four numbers and the sum of the last three numbers from the total sum of the six numbers: 288 - 112 - 123 = 53.

So, the fourth number is 53. The correct answer is "none of these".