Finding the Fourth Proportional to 65,728, 90,704.64 and 42,216.96

Step by Step Solution

1. Step 1: Write the proportion equation
   65,728 : 90,704.64 = 42,216.96 : x
2. Step 2: Convert to fraction form
   65,728/90,704.64 = 42,216.96/x
3. Step 3: Cross multiply
   65,728x = 90,704.64 × 42,216.96
4. Step 4: Simplify right side
   65,728x = 3,829,274,158.69
5. Step 5: Solve for x
   x = 3,829,274,158.69/65,728
6. Step 6: Final answer
   x = 58,259.40