Finding the Fourth Proportional to 1,385.34, 2,067.87 and 1,221.33

Step by Step Solution

1. Step 1: Write the proportion equation
   1,385.34 : 2,067.87 = 1,221.33 : x
2. Step 2: Convert to fraction form
   1,385.34/2,067.87 = 1,221.33/x
3. Step 3: Cross multiply
   1,385.34x = 2,067.87 × 1,221.33
4. Step 4: Simplify right side
   1,385.34x = 2,525,551.67
5. Step 5: Solve for x
   x = 2,525,551.67/1,385.34
6. Step 6: Final answer
   x = 1,823.06