Finding the Fourth Proportional to 2,870.72, 4,305.98 and 818.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,870.72 : 4,305.98 = 818.72 : x
2. Step 2: Convert to fraction form
   2,870.72/4,305.98 = 818.72/x
3. Step 3: Cross multiply
   2,870.72x = 4,305.98 × 818.72
4. Step 4: Simplify right side
   2,870.72x = 3,525,366.32
5. Step 5: Solve for x
   x = 3,525,366.32/2,870.72
6. Step 6: Final answer
   x = 1,228.04