Finding the Fourth Proportional to 78,071.42, 117,035.37 and 28,139.30

Step by Step Solution

1. Step 1: Write the proportion equation
   78,071.42 : 117,035.37 = 28,139.30 : x
2. Step 2: Convert to fraction form
   78,071.42/117,035.37 = 28,139.30/x
3. Step 3: Cross multiply
   78,071.42x = 117,035.37 × 28,139.30
4. Step 4: Simplify right side
   78,071.42x = 3,293,292,801.86
5. Step 5: Solve for x
   x = 3,293,292,801.86/78,071.42
6. Step 6: Final answer
   x = 42,183.08