Finding the Fourth Proportional to 2,387.47, 3,577.31 and 1,215.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,387.47 : 3,577.31 = 1,215.86 : x
2. Step 2: Convert to fraction form
   2,387.47/3,577.31 = 1,215.86/x
3. Step 3: Cross multiply
   2,387.47x = 3,577.31 × 1,215.86
4. Step 4: Simplify right side
   2,387.47x = 4,349,508.14
5. Step 5: Solve for x
   x = 4,349,508.14/2,387.47
6. Step 6: Final answer
   x = 1,821.81