Finding the Fourth Proportional to 1,333.44, 1,997.28 and 990.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,333.44 : 1,997.28 = 990.72 : x
2. Step 2: Convert to fraction form
   1,333.44/1,997.28 = 990.72/x
3. Step 3: Cross multiply
   1,333.44x = 1,997.28 × 990.72
4. Step 4: Simplify right side
   1,333.44x = 1,978,745.24
5. Step 5: Solve for x
   x = 1,978,745.24/1,333.44
6. Step 6: Final answer
   x = 1,483.94