Finding the Fourth Proportional to 1,220.55, 1,826.24 and 810.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,220.55 : 1,826.24 = 810.69 : x
2. Step 2: Convert to fraction form
   1,220.55/1,826.24 = 810.69/x
3. Step 3: Cross multiply
   1,220.55x = 1,826.24 × 810.69
4. Step 4: Simplify right side
   1,220.55x = 1,480,510.45
5. Step 5: Solve for x
   x = 1,480,510.45/1,220.55
6. Step 6: Final answer
   x = 1,212.99