Finding the Fourth Proportional to 1,429.81, 1,983.23 and 1,391.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,429.81 : 1,983.23 = 1,391.87 : x
2. Step 2: Convert to fraction form
   1,429.81/1,983.23 = 1,391.87/x
3. Step 3: Cross multiply
   1,429.81x = 1,983.23 × 1,391.87
4. Step 4: Simplify right side
   1,429.81x = 2,760,396.34
5. Step 5: Solve for x
   x = 2,760,396.34/1,429.81
6. Step 6: Final answer
   x = 1,930.61