Finding the Fourth Proportional to 1,111.58, 1,664.77 and 878.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.58 : 1,664.77 = 878.91 : x
2. Step 2: Convert to fraction form
   1,111.58/1,664.77 = 878.91/x
3. Step 3: Cross multiply
   1,111.58x = 1,664.77 × 878.91
4. Step 4: Simplify right side
   1,111.58x = 1,463,183.00
5. Step 5: Solve for x
   x = 1,463,183.00/1,111.58
6. Step 6: Final answer
   x = 1,316.31