Finding the Fourth Proportional to 1,005.72, 1,388.04 and 586.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.72 : 1,388.04 = 586.10 : x
2. Step 2: Convert to fraction form
   1,005.72/1,388.04 = 586.10/x
3. Step 3: Cross multiply
   1,005.72x = 1,388.04 × 586.10
4. Step 4: Simplify right side
   1,005.72x = 813,530.24
5. Step 5: Solve for x
   x = 813,530.24/1,005.72
6. Step 6: Final answer
   x = 808.90