Finding the Fourth Proportional to 2,070.78, 3,105.72 and 1,238.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,070.78 : 3,105.72 = 1,238.10 : x
2. Step 2: Convert to fraction form
   2,070.78/3,105.72 = 1,238.10/x
3. Step 3: Cross multiply
   2,070.78x = 3,105.72 × 1,238.10
4. Step 4: Simplify right side
   2,070.78x = 3,845,191.93
5. Step 5: Solve for x
   x = 3,845,191.93/2,070.78
6. Step 6: Final answer
   x = 1,856.88