Finding the Fourth Proportional to 1,139.98, 1,707.24 and 1,087.14

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.98 : 1,707.24 = 1,087.14 : x
2. Step 2: Convert to fraction form
   1,139.98/1,707.24 = 1,087.14/x
3. Step 3: Cross multiply
   1,139.98x = 1,707.24 × 1,087.14
4. Step 4: Simplify right side
   1,139.98x = 1,856,008.89
5. Step 5: Solve for x
   x = 1,856,008.89/1,139.98
6. Step 6: Final answer
   x = 1,628.11