Finding the Fourth Proportional to 1,213.89, 1,674.78 and 689.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,213.89 : 1,674.78 = 689.82 : x
2. Step 2: Convert to fraction form
   1,213.89/1,674.78 = 689.82/x
3. Step 3: Cross multiply
   1,213.89x = 1,674.78 × 689.82
4. Step 4: Simplify right side
   1,213.89x = 1,155,296.74
5. Step 5: Solve for x
   x = 1,155,296.74/1,213.89
6. Step 6: Final answer
   x = 951.73