The average of 4 numbers is 100. The sum of the first 3 numbers is 350. Find the 4th number.
Let x be the 4th number.
The average of 4 numbers is given by the sum of all the numbers divided by 4. So, we can write:
(x + 350) / 4 = 100
Multiplying both sides by 4, we get:
x + 350 = 400
Subtracting 350 from both sides, we get:
x = 50
Therefore, the 4th number is 50.