Finding the Fourth Proportional to 2,123.72, 3,184.22 and 823.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.72 : 3,184.22 = 823.80 : x
2. Step 2: Convert to fraction form
   2,123.72/3,184.22 = 823.80/x
3. Step 3: Cross multiply
   2,123.72x = 3,184.22 × 823.80
4. Step 4: Simplify right side
   2,123.72x = 2,623,160.44
5. Step 5: Solve for x
   x = 2,623,160.44/2,123.72
6. Step 6: Final answer
   x = 1,235.17