Finding the Fourth Proportional to 1,818.75, 2,509.69 and 1,221.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,818.75 : 2,509.69 = 1,221.12 : x
2. Step 2: Convert to fraction form
   1,818.75/2,509.69 = 1,221.12/x
3. Step 3: Cross multiply
   1,818.75x = 2,509.69 × 1,221.12
4. Step 4: Simplify right side
   1,818.75x = 3,064,626.55
5. Step 5: Solve for x
   x = 3,064,626.55/1,818.75
6. Step 6: Final answer
   x = 1,685.02