Finding the Fourth Proportional to 2,135.72, 3,204.78 and 981.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,135.72 : 3,204.78 = 981.56 : x
2. Step 2: Convert to fraction form
   2,135.72/3,204.78 = 981.56/x
3. Step 3: Cross multiply
   2,135.72x = 3,204.78 × 981.56
4. Step 4: Simplify right side
   2,135.72x = 3,145,683.86
5. Step 5: Solve for x
   x = 3,145,683.86/2,135.72
6. Step 6: Final answer
   x = 1,472.89