Finding the Fourth Proportional to 2,216.76, 3,325.71 and 830.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,216.76 : 3,325.71 = 830.21 : x
2. Step 2: Convert to fraction form
   2,216.76/3,325.71 = 830.21/x
3. Step 3: Cross multiply
   2,216.76x = 3,325.71 × 830.21
4. Step 4: Simplify right side
   2,216.76x = 2,761,024.18
5. Step 5: Solve for x
   x = 2,761,024.18/2,216.76
6. Step 6: Final answer
   x = 1,245.52