Finding the Fourth Proportional to 31,140.89, 42,981.33 and 19,808.18

Step by Step Solution

1. Step 1: Write the proportion equation
   31,140.89 : 42,981.33 = 19,808.18 : x
2. Step 2: Convert to fraction form
   31,140.89/42,981.33 = 19,808.18/x
3. Step 3: Cross multiply
   31,140.89x = 42,981.33 × 19,808.18
4. Step 4: Simplify right side
   31,140.89x = 851,381,706.37
5. Step 5: Solve for x
   x = 851,381,706.37/31,140.89
6. Step 6: Final answer
   x = 27,339.68