Finding the Fourth Proportional to 112,390.16, 155,092.20 and 64,644.31

Step by Step Solution

1. Step 1: Write the proportion equation
   112,390.16 : 155,092.20 = 64,644.31 : x
2. Step 2: Convert to fraction form
   112,390.16/155,092.20 = 64,644.31/x
3. Step 3: Cross multiply
   112,390.16x = 155,092.20 × 64,644.31
4. Step 4: Simplify right side
   112,390.16x = 10,025,828,255.38
5. Step 5: Solve for x
   x = 10,025,828,255.38/112,390.16
6. Step 6: Final answer
   x = 89,205.57