Finding the Fourth Proportional to 1,279.55, 1,765.86 and 712.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,279.55 : 1,765.86 = 712.42 : x
2. Step 2: Convert to fraction form
   1,279.55/1,765.86 = 712.42/x
3. Step 3: Cross multiply
   1,279.55x = 1,765.86 × 712.42
4. Step 4: Simplify right side
   1,279.55x = 1,258,033.98
5. Step 5: Solve for x
   x = 1,258,033.98/1,279.55
6. Step 6: Final answer
   x = 983.18