Finding the Fourth Proportional to 76,391.61, 105,421.55 and 42,402.29

Step by Step Solution

1. Step 1: Write the proportion equation
   76,391.61 : 105,421.55 = 42,402.29 : x
2. Step 2: Convert to fraction form
   76,391.61/105,421.55 = 42,402.29/x
3. Step 3: Cross multiply
   76,391.61x = 105,421.55 × 42,402.29
4. Step 4: Simplify right side
   76,391.61x = 4,470,114,396.23
5. Step 5: Solve for x
   x = 4,470,114,396.23/76,391.61
6. Step 6: Final answer
   x = 58,515.78