Finding the Fourth Proportional to 2,131.90, 3,198.39 and 671.05

Step by Step Solution

1. Step 1: Write the proportion equation
   2,131.90 : 3,198.39 = 671.05 : x
2. Step 2: Convert to fraction form
   2,131.90/3,198.39 = 671.05/x
3. Step 3: Cross multiply
   2,131.90x = 3,198.39 × 671.05
4. Step 4: Simplify right side
   2,131.90x = 2,146,279.61
5. Step 5: Solve for x
   x = 2,146,279.61/2,131.90
6. Step 6: Final answer
   x = 1,006.74