Finding the Fourth Proportional to 1,015.31, 1,401.38 and 720.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,015.31 : 1,401.38 = 720.67 : x
2. Step 2: Convert to fraction form
   1,015.31/1,401.38 = 720.67/x
3. Step 3: Cross multiply
   1,015.31x = 1,401.38 × 720.67
4. Step 4: Simplify right side
   1,015.31x = 1,009,932.52
5. Step 5: Solve for x
   x = 1,009,932.52/1,015.31
6. Step 6: Final answer
   x = 994.70