Finding the Fourth Proportional to 2,187.31, 3,018.63 and 1,243.09

Step by Step Solution

1. Step 1: Write the proportion equation
   2,187.31 : 3,018.63 = 1,243.09 : x
2. Step 2: Convert to fraction form
   2,187.31/3,018.63 = 1,243.09/x
3. Step 3: Cross multiply
   2,187.31x = 3,018.63 × 1,243.09
4. Step 4: Simplify right side
   2,187.31x = 3,752,428.77
5. Step 5: Solve for x
   x = 3,752,428.77/2,187.31
6. Step 6: Final answer
   x = 1,715.55