Finding the Fourth Proportional to 56,911.62, 78,559.56 and 42,805.20

Step by Step Solution

1. Step 1: Write the proportion equation
   56,911.62 : 78,559.56 = 42,805.20 : x
2. Step 2: Convert to fraction form
   56,911.62/78,559.56 = 42,805.20/x
3. Step 3: Cross multiply
   56,911.62x = 78,559.56 × 42,805.20
4. Step 4: Simplify right side
   56,911.62x = 3,362,757,677.71
5. Step 5: Solve for x
   x = 3,362,757,677.71/56,911.62
6. Step 6: Final answer
   x = 59,087.37