Finding the Fourth Proportional to 2,086.83, 2,878.84 and 1,247.11

Step by Step Solution

1. Step 1: Write the proportion equation
   2,086.83 : 2,878.84 = 1,247.11 : x
2. Step 2: Convert to fraction form
   2,086.83/2,878.84 = 1,247.11/x
3. Step 3: Cross multiply
   2,086.83x = 2,878.84 × 1,247.11
4. Step 4: Simplify right side
   2,086.83x = 3,590,215.76
5. Step 5: Solve for x
   x = 3,590,215.76/2,086.83
6. Step 6: Final answer
   x = 1,720.42