Finding the Fourth Proportional to 1,369.86, 1,890.36 and 772.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,369.86 : 1,890.36 = 772.39 : x
2. Step 2: Convert to fraction form
   1,369.86/1,890.36 = 772.39/x
3. Step 3: Cross multiply
   1,369.86x = 1,890.36 × 772.39
4. Step 4: Simplify right side
   1,369.86x = 1,460,085.71
5. Step 5: Solve for x
   x = 1,460,085.71/1,369.86
6. Step 6: Final answer
   x = 1,065.87