Finding the Fourth Proportional to 1,815.78, 2,502.72 and 1,284.90

Step by Step Solution

1. Step 1: Write the proportion equation
   1,815.78 : 2,502.72 = 1,284.90 : x
2. Step 2: Convert to fraction form
   1,815.78/2,502.72 = 1,284.90/x
3. Step 3: Cross multiply
   1,815.78x = 2,502.72 × 1,284.90
4. Step 4: Simplify right side
   1,815.78x = 3,215,744.93
5. Step 5: Solve for x
   x = 3,215,744.93/1,815.78
6. Step 6: Final answer
   x = 1,771.00