Finding the Fourth Proportional to 2,278.72, 3,144.55 and 1,284.21

Step by Step Solution

1. Step 1: Write the proportion equation
   2,278.72 : 3,144.55 = 1,284.21 : x
2. Step 2: Convert to fraction form
   2,278.72/3,144.55 = 1,284.21/x
3. Step 3: Cross multiply
   2,278.72x = 3,144.55 × 1,284.21
4. Step 4: Simplify right side
   2,278.72x = 4,038,262.56
5. Step 5: Solve for x
   x = 4,038,262.56/2,278.72
6. Step 6: Final answer
   x = 1,772.16