Finding the Fourth Proportional to 1,380, 2,057.82 and 1,279.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380 : 2,057.82 = 1,279.56 : x
2. Step 2: Convert to fraction form
   1,380/2,057.82 = 1,279.56/x
3. Step 3: Cross multiply
   1,380x = 2,057.82 × 1,279.56
4. Step 4: Simplify right side
   1,380x = 2,633,104.16
5. Step 5: Solve for x
   x = 2,633,104.16/1,380
6. Step 6: Final answer
   x = 1,908.05