Finding the Fourth Proportional to 2,085.30, 3,123.90 and 1,429.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.30 : 3,123.90 = 1,429.20 : x
2. Step 2: Convert to fraction form
   2,085.30/3,123.90 = 1,429.20/x
3. Step 3: Cross multiply
   2,085.30x = 3,123.90 × 1,429.20
4. Step 4: Simplify right side
   2,085.30x = 4,464,677.88
5. Step 5: Solve for x
   x = 4,464,677.88/2,085.30
6. Step 6: Final answer
   x = 2,141.02