Finding the Fourth Proportional to 1,100.07, 1,647.52 and 839.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,100.07 : 1,647.52 = 839.76 : x
2. Step 2: Convert to fraction form
   1,100.07/1,647.52 = 839.76/x
3. Step 3: Cross multiply
   1,100.07x = 1,647.52 × 839.76
4. Step 4: Simplify right side
   1,100.07x = 1,383,521.40
5. Step 5: Solve for x
   x = 1,383,521.40/1,100.07
6. Step 6: Final answer
   x = 1,257.67