Finding the Fourth Proportional to 120,398.38, 166,151.01 and 72,642.50

Step by Step Solution

1. Step 1: Write the proportion equation
   120,398.38 : 166,151.01 = 72,642.50 : x
2. Step 2: Convert to fraction form
   120,398.38/166,151.01 = 72,642.50/x
3. Step 3: Cross multiply
   120,398.38x = 166,151.01 × 72,642.50
4. Step 4: Simplify right side
   120,398.38x = 12,069,624,743.93
5. Step 5: Solve for x
   x = 12,069,624,743.93/120,398.38
6. Step 6: Final answer
   x = 100,247.40