Finding the Fourth Proportional to 2,861.78, 4,291.56 and 1,012.55

Step by Step Solution

1. Step 1: Write the proportion equation
   2,861.78 : 4,291.56 = 1,012.55 : x
2. Step 2: Convert to fraction form
   2,861.78/4,291.56 = 1,012.55/x
3. Step 3: Cross multiply
   2,861.78x = 4,291.56 × 1,012.55
4. Step 4: Simplify right side
   2,861.78x = 4,345,397.62
5. Step 5: Solve for x
   x = 4,345,397.62/2,861.78
6. Step 6: Final answer
   x = 1,518.43