Finding the Fourth Proportional to 15,109.20, 22,688.10 and 10,978.20

Step by Step Solution

1. Step 1: Write the proportion equation
   15,109.20 : 22,688.10 = 10,978.20 : x
2. Step 2: Convert to fraction form
   15,109.20/22,688.10 = 10,978.20/x
3. Step 3: Cross multiply
   15,109.20x = 22,688.10 × 10,978.20
4. Step 4: Simplify right side
   15,109.20x = 249,074,499.42
5. Step 5: Solve for x
   x = 249,074,499.42/15,109.20
6. Step 6: Final answer
   x = 16,484.96