Finding the Fourth Proportional to 11,426.72, 15,769.50 and 6,390.88

Step by Step Solution

1. Step 1: Write the proportion equation
   11,426.72 : 15,769.50 = 6,390.88 : x
2. Step 2: Convert to fraction form
   11,426.72/15,769.50 = 6,390.88/x
3. Step 3: Cross multiply
   11,426.72x = 15,769.50 × 6,390.88
4. Step 4: Simplify right side
   11,426.72x = 100,780,982.16
5. Step 5: Solve for x
   x = 100,780,982.16/11,426.72
6. Step 6: Final answer
   x = 8,819.76