Finding the Fourth Proportional to 2,090.35, 3,139.71 and 1,310.86

Step by Step Solution

1. Step 1: Write the proportion equation
   2,090.35 : 3,139.71 = 1,310.86 : x
2. Step 2: Convert to fraction form
   2,090.35/3,139.71 = 1,310.86/x
3. Step 3: Cross multiply
   2,090.35x = 3,139.71 × 1,310.86
4. Step 4: Simplify right side
   2,090.35x = 4,115,720.25
5. Step 5: Solve for x
   x = 4,115,720.25/2,090.35
6. Step 6: Final answer
   x = 1,968.91