Finding the Fourth Proportional to 1,013.31, 1,398.62 and 718.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,013.31 : 1,398.62 = 718.67 : x
2. Step 2: Convert to fraction form
   1,013.31/1,398.62 = 718.67/x
3. Step 3: Cross multiply
   1,013.31x = 1,398.62 × 718.67
4. Step 4: Simplify right side
   1,013.31x = 1,005,147.49
5. Step 5: Solve for x
   x = 1,005,147.49/1,013.31
6. Step 6: Final answer
   x = 991.94