Finding the Fourth Proportional to 2,085.78, 3,127.48 and 851.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.78 : 3,127.48 = 851.74 : x
2. Step 2: Convert to fraction form
   2,085.78/3,127.48 = 851.74/x
3. Step 3: Cross multiply
   2,085.78x = 3,127.48 × 851.74
4. Step 4: Simplify right side
   2,085.78x = 2,663,799.82
5. Step 5: Solve for x
   x = 2,663,799.82/2,085.78
6. Step 6: Final answer
   x = 1,277.12