Finding the Fourth Proportional to 1,212.46, 1,673.13 and 715.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,212.46 : 1,673.13 = 715.30 : x
2. Step 2: Convert to fraction form
   1,212.46/1,673.13 = 715.30/x
3. Step 3: Cross multiply
   1,212.46x = 1,673.13 × 715.30
4. Step 4: Simplify right side
   1,212.46x = 1,196,789.89
5. Step 5: Solve for x
   x = 1,196,789.89/1,212.46
6. Step 6: Final answer
   x = 987.08