Finding the Fourth Proportional to 2,085.06, 3,128.80 and 852.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.06 : 3,128.80 = 852.28 : x
2. Step 2: Convert to fraction form
   2,085.06/3,128.80 = 852.28/x
3. Step 3: Cross multiply
   2,085.06x = 3,128.80 × 852.28
4. Step 4: Simplify right side
   2,085.06x = 2,666,613.66
5. Step 5: Solve for x
   x = 2,666,613.66/2,085.06
6. Step 6: Final answer
   x = 1,278.91