Finding the Fourth Proportional to 1,144.82, 1,715.88 and 939.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,144.82 : 1,715.88 = 939.80 : x
2. Step 2: Convert to fraction form
   1,144.82/1,715.88 = 939.80/x
3. Step 3: Cross multiply
   1,144.82x = 1,715.88 × 939.80
4. Step 4: Simplify right side
   1,144.82x = 1,612,584.02
5. Step 5: Solve for x
   x = 1,612,584.02/1,144.82
6. Step 6: Final answer
   x = 1,408.59