Finding the Fourth Proportional to 1,442.82, 2,162.64 and 921.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,442.82 : 2,162.64 = 921.18 : x
2. Step 2: Convert to fraction form
   1,442.82/2,162.64 = 921.18/x
3. Step 3: Cross multiply
   1,442.82x = 2,162.64 × 921.18
4. Step 4: Simplify right side
   1,442.82x = 1,992,180.72
5. Step 5: Solve for x
   x = 1,992,180.72/1,442.82
6. Step 6: Final answer
   x = 1,380.75