Finding the Fourth Proportional to 1,442.50, 1,991.01 and 821.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,442.50 : 1,991.01 = 821.86 : x
2. Step 2: Convert to fraction form
   1,442.50/1,991.01 = 821.86/x
3. Step 3: Cross multiply
   1,442.50x = 1,991.01 × 821.86
4. Step 4: Simplify right side
   1,442.50x = 1,636,331.48
5. Step 5: Solve for x
   x = 1,636,331.48/1,442.50
6. Step 6: Final answer
   x = 1,134.37