Finding the Fourth Proportional to 65,388.15, 90,245.97 and 39,900.06

Step by Step Solution

1. Step 1: Write the proportion equation
   65,388.15 : 90,245.97 = 39,900.06 : x
2. Step 2: Convert to fraction form
   65,388.15/90,245.97 = 39,900.06/x
3. Step 3: Cross multiply
   65,388.15x = 90,245.97 × 39,900.06
4. Step 4: Simplify right side
   65,388.15x = 3,600,819,617.76
5. Step 5: Solve for x
   x = 3,600,819,617.76/65,388.15
6. Step 6: Final answer
   x = 55,068.38