Finding the Fourth Proportional to 123,378.31, 170,251.81 and 72,385.71

Step by Step Solution

1. Step 1: Write the proportion equation
   123,378.31 : 170,251.81 = 72,385.71 : x
2. Step 2: Convert to fraction form
   123,378.31/170,251.81 = 72,385.71/x
3. Step 3: Cross multiply
   123,378.31x = 170,251.81 × 72,385.71
4. Step 4: Simplify right side
   123,378.31x = 12,323,798,145.64
5. Step 5: Solve for x
   x = 12,323,798,145.64/123,378.31
6. Step 6: Final answer
   x = 99,886.26