Finding the Fourth Proportional to 2,070.78, 3,107.72 and 1,291.92

Step by Step Solution

1. Step 1: Write the proportion equation
   2,070.78 : 3,107.72 = 1,291.92 : x
2. Step 2: Convert to fraction form
   2,070.78/3,107.72 = 1,291.92/x
3. Step 3: Cross multiply
   2,070.78x = 3,107.72 × 1,291.92
4. Step 4: Simplify right side
   2,070.78x = 4,014,925.62
5. Step 5: Solve for x
   x = 4,014,925.62/2,070.78
6. Step 6: Final answer
   x = 1,938.85