Finding the Fourth Proportional to 2,385.08, 3,291.32 and 1,390.42

Step by Step Solution

1. Step 1: Write the proportion equation
   2,385.08 : 3,291.32 = 1,390.42 : x
2. Step 2: Convert to fraction form
   2,385.08/3,291.32 = 1,390.42/x
3. Step 3: Cross multiply
   2,385.08x = 3,291.32 × 1,390.42
4. Step 4: Simplify right side
   2,385.08x = 4,576,312.40
5. Step 5: Solve for x
   x = 4,576,312.40/2,385.08
6. Step 6: Final answer
   x = 1,918.73