Finding the Fourth Proportional to 31,049.46, 42,849.20 and 21,991.05

Step by Step Solution

1. Step 1: Write the proportion equation
   31,049.46 : 42,849.20 = 21,991.05 : x
2. Step 2: Convert to fraction form
   31,049.46/42,849.20 = 21,991.05/x
3. Step 3: Cross multiply
   31,049.46x = 42,849.20 × 21,991.05
4. Step 4: Simplify right side
   31,049.46x = 942,298,899.66
5. Step 5: Solve for x
   x = 942,298,899.66/31,049.46
6. Step 6: Final answer
   x = 30,348.32