Finding the Fourth Proportional to 1,439.89, 1,987.13 and 850.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,439.89 : 1,987.13 = 850.52 : x
2. Step 2: Convert to fraction form
   1,439.89/1,987.13 = 850.52/x
3. Step 3: Cross multiply
   1,439.89x = 1,987.13 × 850.52
4. Step 4: Simplify right side
   1,439.89x = 1,690,093.81
5. Step 5: Solve for x
   x = 1,690,093.81/1,439.89
6. Step 6: Final answer
   x = 1,173.77