Finding the Fourth Proportional to 1,315.43, 1,975.78 and 822.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.43 : 1,975.78 = 822.72 : x
2. Step 2: Convert to fraction form
   1,315.43/1,975.78 = 822.72/x
3. Step 3: Cross multiply
   1,315.43x = 1,975.78 × 822.72
4. Step 4: Simplify right side
   1,315.43x = 1,625,499.73
5. Step 5: Solve for x
   x = 1,625,499.73/1,315.43
6. Step 6: Final answer
   x = 1,235.72