Finding the Fourth Proportional to 31,890, 44,019.72 and 21,982.80

Step by Step Solution

1. Step 1: Write the proportion equation
   31,890 : 44,019.72 = 21,982.80 : x
2. Step 2: Convert to fraction form
   31,890/44,019.72 = 21,982.80/x
3. Step 3: Cross multiply
   31,890x = 44,019.72 × 21,982.80
4. Step 4: Simplify right side
   31,890x = 967,676,700.82
5. Step 5: Solve for x
   x = 967,676,700.82/31,890
6. Step 6: Final answer
   x = 30,344.21