Finding the Fourth Proportional to 1,392.09, 1,921.83 and 888.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,392.09 : 1,921.83 = 888.45 : x
2. Step 2: Convert to fraction form
   1,392.09/1,921.83 = 888.45/x
3. Step 3: Cross multiply
   1,392.09x = 1,921.83 × 888.45
4. Step 4: Simplify right side
   1,392.09x = 1,707,449.86
5. Step 5: Solve for x
   x = 1,707,449.86/1,392.09
6. Step 6: Final answer
   x = 1,226.54