Finding the Fourth Proportional to 76,970.76, 106,221.45 and 42,978.10

Step by Step Solution

1. Step 1: Write the proportion equation
   76,970.76 : 106,221.45 = 42,978.10 : x
2. Step 2: Convert to fraction form
   76,970.76/106,221.45 = 42,978.10/x
3. Step 3: Cross multiply
   76,970.76x = 106,221.45 × 42,978.10
4. Step 4: Simplify right side
   76,970.76x = 4,565,195,834.69
5. Step 5: Solve for x
   x = 4,565,195,834.69/76,970.76
6. Step 6: Final answer
   x = 59,310.78