Finding the Fourth Proportional to 1,015.83, 1,401.72 and 720.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,015.83 : 1,401.72 = 720.99 : x
2. Step 2: Convert to fraction form
   1,015.83/1,401.72 = 720.99/x
3. Step 3: Cross multiply
   1,015.83x = 1,401.72 × 720.99
4. Step 4: Simplify right side
   1,015.83x = 1,010,626.10
5. Step 5: Solve for x
   x = 1,010,626.10/1,015.83
6. Step 6: Final answer
   x = 994.88