Finding the Fourth Proportional to 2,083.86, 3,123.68 and 1,388.79

Step by Step Solution

1. Step 1: Write the proportion equation
   2,083.86 : 3,123.68 = 1,388.79 : x
2. Step 2: Convert to fraction form
   2,083.86/3,123.68 = 1,388.79/x
3. Step 3: Cross multiply
   2,083.86x = 3,123.68 × 1,388.79
4. Step 4: Simplify right side
   2,083.86x = 4,338,128.60
5. Step 5: Solve for x
   x = 4,338,128.60/2,083.86
6. Step 6: Final answer
   x = 2,081.78