Finding the Fourth Proportional to 1,333.10, 1,839.55 and 1,288.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,333.10 : 1,839.55 = 1,288.31 : x
2. Step 2: Convert to fraction form
   1,333.10/1,839.55 = 1,288.31/x
3. Step 3: Cross multiply
   1,333.10x = 1,839.55 × 1,288.31
4. Step 4: Simplify right side
   1,333.10x = 2,369,907.58
5. Step 5: Solve for x
   x = 2,369,907.58/1,333.10
6. Step 6: Final answer
   x = 1,777.75