Finding the Fourth Proportional to 2,565, 3,846.69 and 921.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,565 : 3,846.69 = 921.78 : x
2. Step 2: Convert to fraction form
   2,565/3,846.69 = 921.78/x
3. Step 3: Cross multiply
   2,565x = 3,846.69 × 921.78
4. Step 4: Simplify right side
   2,565x = 3,545,801.91
5. Step 5: Solve for x
   x = 3,545,801.91/2,565
6. Step 6: Final answer
   x = 1,382.38