Finding the Fourth Proportional to 1,011.42, 1,395.72 and 618.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,011.42 : 1,395.72 = 618.48 : x
2. Step 2: Convert to fraction form
   1,011.42/1,395.72 = 618.48/x
3. Step 3: Cross multiply
   1,011.42x = 1,395.72 × 618.48
4. Step 4: Simplify right side
   1,011.42x = 863,224.91
5. Step 5: Solve for x
   x = 863,224.91/1,011.42
6. Step 6: Final answer
   x = 853.48