Finding the Fourth Proportional to 85,792.32, 128,688.84 and 83,718.72

Step by Step Solution

1. Step 1: Write the proportion equation
   85,792.32 : 128,688.84 = 83,718.72 : x
2. Step 2: Convert to fraction form
   85,792.32/128,688.84 = 83,718.72/x
3. Step 3: Cross multiply
   85,792.32x = 128,688.84 × 83,718.72
4. Step 4: Simplify right side
   85,792.32x = 10,773,664,963.08
5. Step 5: Solve for x
   x = 10,773,664,963.08/85,792.32
6. Step 6: Final answer
   x = 125,578.43