Finding the Fourth Proportional to 1,219.45, 1,682.43 and 688.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,219.45 : 1,682.43 = 688.27 : x
2. Step 2: Convert to fraction form
   1,219.45/1,682.43 = 688.27/x
3. Step 3: Cross multiply
   1,219.45x = 1,682.43 × 688.27
4. Step 4: Simplify right side
   1,219.45x = 1,157,966.10
5. Step 5: Solve for x
   x = 1,157,966.10/1,219.45
6. Step 6: Final answer
   x = 949.58