Finding the Fourth Proportional to 57,412.69, 78,735.17 and 55,017.91

Step by Step Solution

1. Step 1: Write the proportion equation
   57,412.69 : 78,735.17 = 55,017.91 : x
2. Step 2: Convert to fraction form
   57,412.69/78,735.17 = 55,017.91/x
3. Step 3: Cross multiply
   57,412.69x = 78,735.17 × 55,017.91
4. Step 4: Simplify right side
   57,412.69x = 4,331,844,496.89
5. Step 5: Solve for x
   x = 4,331,844,496.89/57,412.69
6. Step 6: Final answer
   x = 75,450.99