Finding the Fourth Proportional to 2,215.30, 3,321.86 and 1,291.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,215.30 : 3,321.86 = 1,291.09 : x
2. Step 2: Convert to fraction form
   2,215.30/3,321.86 = 1,291.09/x
3. Step 3: Cross multiply
   2,215.30x = 3,321.86 × 1,291.09
4. Step 4: Simplify right side
   2,215.30x = 4,288,818.96
5. Step 5: Solve for x
   x = 4,288,818.96/2,215.30
6. Step 6: Final answer
   x = 1,936.00