Finding the Fourth Proportional to 1,212.27, 1,673.19 and 688.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,212.27 : 1,673.19 = 688.59 : x
2. Step 2: Convert to fraction form
   1,212.27/1,673.19 = 688.59/x
3. Step 3: Cross multiply
   1,212.27x = 1,673.19 × 688.59
4. Step 4: Simplify right side
   1,212.27x = 1,152,141.90
5. Step 5: Solve for x
   x = 1,152,141.90/1,212.27
6. Step 6: Final answer
   x = 950.40