Finding the Fourth Proportional to 56,642.38, 78,168.47 and 31,149.79

Step by Step Solution

1. Step 1: Write the proportion equation
   56,642.38 : 78,168.47 = 31,149.79 : x
2. Step 2: Convert to fraction form
   56,642.38/78,168.47 = 31,149.79/x
3. Step 3: Cross multiply
   56,642.38x = 78,168.47 × 31,149.79
4. Step 4: Simplify right side
   56,642.38x = 2,434,931,425.12
5. Step 5: Solve for x
   x = 2,434,931,425.12/56,642.38
6. Step 6: Final answer
   x = 42,987.80