Finding the Fourth Proportional to 1,390.14, 1,918.06 and 830.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.14 : 1,918.06 = 830.82 : x
2. Step 2: Convert to fraction form
   1,390.14/1,918.06 = 830.82/x
3. Step 3: Cross multiply
   1,390.14x = 1,918.06 × 830.82
4. Step 4: Simplify right side
   1,390.14x = 1,593,562.61
5. Step 5: Solve for x
   x = 1,593,562.61/1,390.14
6. Step 6: Final answer
   x = 1,146.33