Finding the Fourth Proportional to 72,175.52, 99,602.88 and 39,909.72

Step by Step Solution

1. Step 1: Write the proportion equation
   72,175.52 : 99,602.88 = 39,909.72 : x
2. Step 2: Convert to fraction form
   72,175.52/99,602.88 = 39,909.72/x
3. Step 3: Cross multiply
   72,175.52x = 99,602.88 × 39,909.72
4. Step 4: Simplify right side
   72,175.52x = 3,975,123,051.99
5. Step 5: Solve for x
   x = 3,975,123,051.99/72,175.52
6. Step 6: Final answer
   x = 55,075.78