Finding the Fourth Proportional to 80,609.40, 120,947.16 and 42,648.78

Step by Step Solution

1. Step 1: Write the proportion equation
   80,609.40 : 120,947.16 = 42,648.78 : x
2. Step 2: Convert to fraction form
   80,609.40/120,947.16 = 42,648.78/x
3. Step 3: Cross multiply
   80,609.40x = 120,947.16 × 42,648.78
4. Step 4: Simplify right side
   80,609.40x = 5,158,248,818.46
5. Step 5: Solve for x
   x = 5,158,248,818.46/80,609.40
6. Step 6: Final answer
   x = 63,990.66