Finding the Fourth Proportional to 145,312.57, 200,549.28 and 81,649

Step by Step Solution

1. Step 1: Write the proportion equation
   145,312.57 : 200,549.28 = 81,649 : x
2. Step 2: Convert to fraction form
   145,312.57/200,549.28 = 81,649/x
3. Step 3: Cross multiply
   145,312.57x = 200,549.28 × 81,649
4. Step 4: Simplify right side
   145,312.57x = 16,374,648,162.72
5. Step 5: Solve for x
   x = 16,374,648,162.72/145,312.57
6. Step 6: Final answer
   x = 112,685.70