Finding the Fourth Proportional to 1,369.07, 1,889.33 and 779.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.07 : 1,889.33 = 779.61 : x
2. Step 2: Convert to fraction form
   1,369.07/1,889.33 = 779.61/x
3. Step 3: Cross multiply
   1,369.07x = 1,889.33 × 779.61
4. Step 4: Simplify right side
   1,369.07x = 1,472,936.66
5. Step 5: Solve for x
   x = 1,472,936.66/1,369.07
6. Step 6: Final answer
   x = 1,075.87