Finding the Fourth Proportional to 1,145.56, 1,582.38 and 878.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.56 : 1,582.38 = 878.38 : x
2. Step 2: Convert to fraction form
   1,145.56/1,582.38 = 878.38/x
3. Step 3: Cross multiply
   1,145.56x = 1,582.38 × 878.38
4. Step 4: Simplify right side
   1,145.56x = 1,389,930.94
5. Step 5: Solve for x
   x = 1,389,930.94/1,145.56
6. Step 6: Final answer
   x = 1,213.32