Finding the Fourth Proportional to 28,139.73, 42,215.84 and 10,609.71

Step by Step Solution

1. Step 1: Write the proportion equation
   28,139.73 : 42,215.84 = 10,609.71 : x
2. Step 2: Convert to fraction form
   28,139.73/42,215.84 = 10,609.71/x
3. Step 3: Cross multiply
   28,139.73x = 42,215.84 × 10,609.71
4. Step 4: Simplify right side
   28,139.73x = 447,897,766.76
5. Step 5: Solve for x
   x = 447,897,766.76/28,139.73
6. Step 6: Final answer
   x = 15,916.92