Finding the Fourth Proportional to 1,071.89, 1,478.31 and 850.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,071.89 : 1,478.31 = 850.49 : x
2. Step 2: Convert to fraction form
   1,071.89/1,478.31 = 850.49/x
3. Step 3: Cross multiply
   1,071.89x = 1,478.31 × 850.49
4. Step 4: Simplify right side
   1,071.89x = 1,257,287.87
5. Step 5: Solve for x
   x = 1,257,287.87/1,071.89
6. Step 6: Final answer
   x = 1,172.96