Finding the Fourth Proportional to 2,123.35, 3,180.88 and 1,390.70

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.35 : 3,180.88 = 1,390.70 : x
2. Step 2: Convert to fraction form
   2,123.35/3,180.88 = 1,390.70/x
3. Step 3: Cross multiply
   2,123.35x = 3,180.88 × 1,390.70
4. Step 4: Simplify right side
   2,123.35x = 4,423,642.86
5. Step 5: Solve for x
   x = 4,423,642.86/2,123.35
6. Step 6: Final answer
   x = 2,083.34