Finding the Fourth Proportional to 78,630.21, 108,509.61 and 42,820.47

Step by Step Solution

1. Step 1: Write the proportion equation
   78,630.21 : 108,509.61 = 42,820.47 : x
2. Step 2: Convert to fraction form
   78,630.21/108,509.61 = 42,820.47/x
3. Step 3: Cross multiply
   78,630.21x = 108,509.61 × 42,820.47
4. Step 4: Simplify right side
   78,630.21x = 4,646,432,499.72
5. Step 5: Solve for x
   x = 4,646,432,499.72/78,630.21
6. Step 6: Final answer
   x = 59,092.21