Finding the Fourth Proportional to 1,369.31, 1,889.60 and 771.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.31 : 1,889.60 = 771.83 : x
2. Step 2: Convert to fraction form
   1,369.31/1,889.60 = 771.83/x
3. Step 3: Cross multiply
   1,369.31x = 1,889.60 × 771.83
4. Step 4: Simplify right side
   1,369.31x = 1,458,449.97
5. Step 5: Solve for x
   x = 1,458,449.97/1,369.31
6. Step 6: Final answer
   x = 1,065.10