Finding the Fourth Proportional to 2,087.76, 3,131.82 and 855.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,087.76 : 3,131.82 = 855.24 : x
2. Step 2: Convert to fraction form
   2,087.76/3,131.82 = 855.24/x
3. Step 3: Cross multiply
   2,087.76x = 3,131.82 × 855.24
4. Step 4: Simplify right side
   2,087.76x = 2,678,457.74
5. Step 5: Solve for x
   x = 2,678,457.74/2,087.76
6. Step 6: Final answer
   x = 1,282.93