Finding the Fourth Proportional to 1,142.54, 1,578.42 and 1,077.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,142.54 : 1,578.42 = 1,077.74 : x
2. Step 2: Convert to fraction form
   1,142.54/1,578.42 = 1,077.74/x
3. Step 3: Cross multiply
   1,142.54x = 1,578.42 × 1,077.74
4. Step 4: Simplify right side
   1,142.54x = 1,701,126.37
5. Step 5: Solve for x
   x = 1,701,126.37/1,142.54
6. Step 6: Final answer
   x = 1,488.90