Finding the Fourth Proportional to 1,340.22, 2,011.72 and 820.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,340.22 : 2,011.72 = 820.58 : x
2. Step 2: Convert to fraction form
   1,340.22/2,011.72 = 820.58/x
3. Step 3: Cross multiply
   1,340.22x = 2,011.72 × 820.58
4. Step 4: Simplify right side
   1,340.22x = 1,650,777.20
5. Step 5: Solve for x
   x = 1,650,777.20/1,340.22
6. Step 6: Final answer
   x = 1,231.72