Finding the Fourth Proportional to 1,222.49, 1,687.62 and 698.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.49 : 1,687.62 = 698.42 : x
2. Step 2: Convert to fraction form
   1,222.49/1,687.62 = 698.42/x
3. Step 3: Cross multiply
   1,222.49x = 1,687.62 × 698.42
4. Step 4: Simplify right side
   1,222.49x = 1,178,667.56
5. Step 5: Solve for x
   x = 1,178,667.56/1,222.49
6. Step 6: Final answer
   x = 964.15