Finding the Fourth Proportional to 1,217.94, 1,680.76 and 693.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,217.94 : 1,680.76 = 693.98 : x
2. Step 2: Convert to fraction form
   1,217.94/1,680.76 = 693.98/x
3. Step 3: Cross multiply
   1,217.94x = 1,680.76 × 693.98
4. Step 4: Simplify right side
   1,217.94x = 1,166,413.82
5. Step 5: Solve for x
   x = 1,166,413.82/1,217.94
6. Step 6: Final answer
   x = 957.69