Finding the Fourth Proportional to 72,441.61, 99,945.79 and 42,220.02

Step by Step Solution

1. Step 1: Write the proportion equation
   72,441.61 : 99,945.79 = 42,220.02 : x
2. Step 2: Convert to fraction form
   72,441.61/99,945.79 = 42,220.02/x
3. Step 3: Cross multiply
   72,441.61x = 99,945.79 × 42,220.02
4. Step 4: Simplify right side
   72,441.61x = 4,219,713,252.72
5. Step 5: Solve for x
   x = 4,219,713,252.72/72,441.61
6. Step 6: Final answer
   x = 58,249.85