Finding the Fourth Proportional to 1,147.57, 1,719.83 and 839.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,147.57 : 1,719.83 = 839.87 : x
2. Step 2: Convert to fraction form
   1,147.57/1,719.83 = 839.87/x
3. Step 3: Cross multiply
   1,147.57x = 1,719.83 × 839.87
4. Step 4: Simplify right side
   1,147.57x = 1,444,433.57
5. Step 5: Solve for x
   x = 1,444,433.57/1,147.57
6. Step 6: Final answer
   x = 1,258.69