Finding the Fourth Proportional to 77,311.82, 105,890.90 and 72,772.58

Step by Step Solution

1. Step 1: Write the proportion equation
   77,311.82 : 105,890.90 = 72,772.58 : x
2. Step 2: Convert to fraction form
   77,311.82/105,890.90 = 72,772.58/x
3. Step 3: Cross multiply
   77,311.82x = 105,890.90 × 72,772.58
4. Step 4: Simplify right side
   77,311.82x = 7,705,953,991.52
5. Step 5: Solve for x
   x = 7,705,953,991.52/77,311.82
6. Step 6: Final answer
   x = 99,673.68