Finding the Fourth Proportional to 14,435.50, 19,921 and 7,811.50

Step by Step Solution

1. Step 1: Write the proportion equation
   14,435.50 : 19,921 = 7,811.50 : x
2. Step 2: Convert to fraction form
   14,435.50/19,921 = 7,811.50/x
3. Step 3: Cross multiply
   14,435.50x = 19,921 × 7,811.50
4. Step 4: Simplify right side
   14,435.50x = 155,612,891.50
5. Step 5: Solve for x
   x = 155,612,891.50/14,435.50
6. Step 6: Final answer
   x = 10,779.88