Finding the Fourth Proportional to 1,333.60, 1,997.31 and 1,287.46

Step by Step Solution

1. Step 1: Write the proportion equation
   1,333.60 : 1,997.31 = 1,287.46 : x
2. Step 2: Convert to fraction form
   1,333.60/1,997.31 = 1,287.46/x
3. Step 3: Cross multiply
   1,333.60x = 1,997.31 × 1,287.46
4. Step 4: Simplify right side
   1,333.60x = 2,571,456.73
5. Step 5: Solve for x
   x = 2,571,456.73/1,333.60
6. Step 6: Final answer
   x = 1,928.21