Finding the Fourth Proportional to 1,085.82, 1,626.21 and 853.08

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.82 : 1,626.21 = 853.08 : x
2. Step 2: Convert to fraction form
   1,085.82/1,626.21 = 853.08/x
3. Step 3: Cross multiply
   1,085.82x = 1,626.21 × 853.08
4. Step 4: Simplify right side
   1,085.82x = 1,387,287.23
5. Step 5: Solve for x
   x = 1,387,287.23/1,085.82
6. Step 6: Final answer
   x = 1,277.64