Finding the Fourth Proportional to 2,215.86, 3,320.13 and 981.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,215.86 : 3,320.13 = 981.42 : x
2. Step 2: Convert to fraction form
   2,215.86/3,320.13 = 981.42/x
3. Step 3: Cross multiply
   2,215.86x = 3,320.13 × 981.42
4. Step 4: Simplify right side
   2,215.86x = 3,258,441.98
5. Step 5: Solve for x
   x = 3,258,441.98/2,215.86
6. Step 6: Final answer
   x = 1,470.51