Finding the Fourth Proportional to 2,085.16, 3,128.88 and 852.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,085.16 : 3,128.88 = 852.28 : x
2. Step 2: Convert to fraction form
   2,085.16/3,128.88 = 852.28/x
3. Step 3: Cross multiply
   2,085.16x = 3,128.88 × 852.28
4. Step 4: Simplify right side
   2,085.16x = 2,666,681.85
5. Step 5: Solve for x
   x = 2,666,681.85/2,085.16
6. Step 6: Final answer
   x = 1,278.89