Finding the Fourth Proportional to 78,031.52, 107,683.20 and 42,221.60

Step by Step Solution

1. Step 1: Write the proportion equation
   78,031.52 : 107,683.20 = 42,221.60 : x
2. Step 2: Convert to fraction form
   78,031.52/107,683.20 = 42,221.60/x
3. Step 3: Cross multiply
   78,031.52x = 107,683.20 × 42,221.60
4. Step 4: Simplify right side
   78,031.52x = 4,546,556,997.12
5. Step 5: Solve for x
   x = 4,546,556,997.12/78,031.52
6. Step 6: Final answer
   x = 58,265.65