Finding the Fourth Proportional to 1,245.42, 1,718.67 and 685.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,245.42 : 1,718.67 = 685.86 : x
2. Step 2: Convert to fraction form
   1,245.42/1,718.67 = 685.86/x
3. Step 3: Cross multiply
   1,245.42x = 1,718.67 × 685.86
4. Step 4: Simplify right side
   1,245.42x = 1,178,767.01
5. Step 5: Solve for x
   x = 1,178,767.01/1,245.42
6. Step 6: Final answer
   x = 946.48