Finding the Fourth Proportional to 1,256.78, 1,734.17 and 697.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,256.78 : 1,734.17 = 697.23 : x
2. Step 2: Convert to fraction form
   1,256.78/1,734.17 = 697.23/x
3. Step 3: Cross multiply
   1,256.78x = 1,734.17 × 697.23
4. Step 4: Simplify right side
   1,256.78x = 1,209,111.86
5. Step 5: Solve for x
   x = 1,209,111.86/1,256.78
6. Step 6: Final answer
   x = 962.07