Finding the Fourth Proportional to 1,005.99, 1,509.89 and 842.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.99 : 1,509.89 = 842.49 : x
2. Step 2: Convert to fraction form
   1,005.99/1,509.89 = 842.49/x
3. Step 3: Cross multiply
   1,005.99x = 1,509.89 × 842.49
4. Step 4: Simplify right side
   1,005.99x = 1,272,067.23
5. Step 5: Solve for x
   x = 1,272,067.23/1,005.99
6. Step 6: Final answer
   x = 1,264.49