Finding the Fourth Proportional to 112,386.85, 155,087.63 and 64,640.99

Step by Step Solution

1. Step 1: Write the proportion equation
   112,386.85 : 155,087.63 = 64,640.99 : x
2. Step 2: Convert to fraction form
   112,386.85/155,087.63 = 64,640.99/x
3. Step 3: Cross multiply
   112,386.85x = 155,087.63 × 64,640.99
4. Step 4: Simplify right side
   112,386.85x = 10,025,018,246.87
5. Step 5: Solve for x
   x = 10,025,018,246.87/112,386.85
6. Step 6: Final answer
   x = 89,200.99