Finding the Fourth Proportional to 1,111.86, 1,664.82 and 881.28

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.86 : 1,664.82 = 881.28 : x
2. Step 2: Convert to fraction form
   1,111.86/1,664.82 = 881.28/x
3. Step 3: Cross multiply
   1,111.86x = 1,664.82 × 881.28
4. Step 4: Simplify right side
   1,111.86x = 1,467,172.57
5. Step 5: Solve for x
   x = 1,467,172.57/1,111.86
6. Step 6: Final answer
   x = 1,319.57