Finding the Fourth Proportional to 7,086.31, 10,620.21 and 2,921.56

Step by Step Solution

1. Step 1: Write the proportion equation
   7,086.31 : 10,620.21 = 2,921.56 : x
2. Step 2: Convert to fraction form
   7,086.31/10,620.21 = 2,921.56/x
3. Step 3: Cross multiply
   7,086.31x = 10,620.21 × 2,921.56
4. Step 4: Simplify right side
   7,086.31x = 31,027,580.73
5. Step 5: Solve for x
   x = 31,027,580.73/7,086.31
6. Step 6: Final answer
   x = 4,378.52