Finding the Fourth Proportional to 76,405, 105,438.06 and 42,413.76

Step by Step Solution

1. Step 1: Write the proportion equation
   76,405 : 105,438.06 = 42,413.76 : x
2. Step 2: Convert to fraction form
   76,405/105,438.06 = 42,413.76/x
3. Step 3: Cross multiply
   76,405x = 105,438.06 × 42,413.76
4. Step 4: Simplify right side
   76,405x = 4,472,024,571.71
5. Step 5: Solve for x
   x = 4,472,024,571.71/76,405
6. Step 6: Final answer
   x = 58,530.52