Finding the Fourth Proportional to 1,321.78, 1,824.78 and 902.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,321.78 : 1,824.78 = 902.75 : x
2. Step 2: Convert to fraction form
   1,321.78/1,824.78 = 902.75/x
3. Step 3: Cross multiply
   1,321.78x = 1,824.78 × 902.75
4. Step 4: Simplify right side
   1,321.78x = 1,647,320.15
5. Step 5: Solve for x
   x = 1,647,320.15/1,321.78
6. Step 6: Final answer
   x = 1,246.29