Finding the Fourth Proportional to 25,978.05, 38,976.12 and 8,211.42

Step by Step Solution

1. Step 1: Write the proportion equation
   25,978.05 : 38,976.12 = 8,211.42 : x
2. Step 2: Convert to fraction form
   25,978.05/38,976.12 = 8,211.42/x
3. Step 3: Cross multiply
   25,978.05x = 38,976.12 × 8,211.42
4. Step 4: Simplify right side
   25,978.05x = 320,049,291.29
5. Step 5: Solve for x
   x = 320,049,291.29/25,978.05
6. Step 6: Final answer
   x = 12,319.99