Finding the Fourth Proportional to 72,418.08, 99,936.72 and 42,221.28

Step by Step Solution

1. Step 1: Write the proportion equation
   72,418.08 : 99,936.72 = 42,221.28 : x
2. Step 2: Convert to fraction form
   72,418.08/99,936.72 = 42,221.28/x
3. Step 3: Cross multiply
   72,418.08x = 99,936.72 × 42,221.28
4. Step 4: Simplify right side
   72,418.08x = 4,219,456,237.40
5. Step 5: Solve for x
   x = 4,219,456,237.40/72,418.08
6. Step 6: Final answer
   x = 58,265.23