Finding the Fourth Proportional to 140,819.16, 210,956.55 and 78,300.12

Step by Step Solution

1. Step 1: Write the proportion equation
   140,819.16 : 210,956.55 = 78,300.12 : x
2. Step 2: Convert to fraction form
   140,819.16/210,956.55 = 78,300.12/x
3. Step 3: Cross multiply
   140,819.16x = 210,956.55 × 78,300.12
4. Step 4: Simplify right side
   140,819.16x = 16,517,923,179.79
5. Step 5: Solve for x
   x = 16,517,923,179.79/140,819.16
6. Step 6: Final answer
   x = 117,298.83