Finding the Fourth Proportional to 1,139.96, 1,713.86 and 1,108.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.96 : 1,713.86 = 1,108.87 : x
2. Step 2: Convert to fraction form
   1,139.96/1,713.86 = 1,108.87/x
3. Step 3: Cross multiply
   1,139.96x = 1,713.86 × 1,108.87
4. Step 4: Simplify right side
   1,139.96x = 1,900,447.94
5. Step 5: Solve for x
   x = 1,900,447.94/1,139.96
6. Step 6: Final answer
   x = 1,667.12