Finding the Fourth Proportional to 1,212.69, 1,673.46 and 715.35

Step by Step Solution

1. Step 1: Write the proportion equation
   1,212.69 : 1,673.46 = 715.35 : x
2. Step 2: Convert to fraction form
   1,212.69/1,673.46 = 715.35/x
3. Step 3: Cross multiply
   1,212.69x = 1,673.46 × 715.35
4. Step 4: Simplify right side
   1,212.69x = 1,197,109.61
5. Step 5: Solve for x
   x = 1,197,109.61/1,212.69
6. Step 6: Final answer
   x = 987.15