Finding the Fourth Proportional to 56,640.24, 78,154.88 and 31,147.64

Step by Step Solution

1. Step 1: Write the proportion equation
   56,640.24 : 78,154.88 = 31,147.64 : x
2. Step 2: Convert to fraction form
   56,640.24/78,154.88 = 31,147.64/x
3. Step 3: Cross multiply
   56,640.24x = 78,154.88 × 31,147.64
4. Step 4: Simplify right side
   56,640.24x = 2,434,340,066.48
5. Step 5: Solve for x
   x = 2,434,340,066.48/56,640.24
6. Step 6: Final answer
   x = 42,978.99