Finding the Fourth Proportional to 65,436.69, 90,358.77 and 63,320.78

Step by Step Solution

1. Step 1: Write the proportion equation
   65,436.69 : 90,358.77 = 63,320.78 : x
2. Step 2: Convert to fraction form
   65,436.69/90,358.77 = 63,320.78/x
3. Step 3: Cross multiply
   65,436.69x = 90,358.77 × 63,320.78
4. Step 4: Simplify right side
   65,436.69x = 5,721,587,344.45
5. Step 5: Solve for x
   x = 5,721,587,344.45/65,436.69
6. Step 6: Final answer
   x = 87,436.99