Finding the Fourth Proportional to 15,353.91, 21,200.72 and 9,979.02

Step by Step Solution

1. Step 1: Write the proportion equation
   15,353.91 : 21,200.72 = 9,979.02 : x
2. Step 2: Convert to fraction form
   15,353.91/21,200.72 = 9,979.02/x
3. Step 3: Cross multiply
   15,353.91x = 21,200.72 × 9,979.02
4. Step 4: Simplify right side
   15,353.91x = 211,562,359.00
5. Step 5: Solve for x
   x = 211,562,359.00/15,353.91
6. Step 6: Final answer
   x = 13,779.05