Finding the Fourth Proportional to 21,016.76, 31,527.54 and 6,978.68

Step by Step Solution

1. Step 1: Write the proportion equation
   21,016.76 : 31,527.54 = 6,978.68 : x
2. Step 2: Convert to fraction form
   21,016.76/31,527.54 = 6,978.68/x
3. Step 3: Cross multiply
   21,016.76x = 31,527.54 × 6,978.68
4. Step 4: Simplify right side
   21,016.76x = 220,020,612.85
5. Step 5: Solve for x
   x = 220,020,612.85/21,016.76
6. Step 6: Final answer
   x = 10,468.82