Finding the Fourth Proportional to 2,215.20, 3,316.86 and 1,238.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,215.20 : 3,316.86 = 1,238.52 : x
2. Step 2: Convert to fraction form
   2,215.20/3,316.86 = 1,238.52/x
3. Step 3: Cross multiply
   2,215.20x = 3,316.86 × 1,238.52
4. Step 4: Simplify right side
   2,215.20x = 4,107,997.45
5. Step 5: Solve for x
   x = 4,107,997.45/2,215.20
6. Step 6: Final answer
   x = 1,854.46