Finding the Fourth Proportional to 1,779.89, 2,669.81 and 805.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,779.89 : 2,669.81 = 805.31 : x
2. Step 2: Convert to fraction form
   1,779.89/2,669.81 = 805.31/x
3. Step 3: Cross multiply
   1,779.89x = 2,669.81 × 805.31
4. Step 4: Simplify right side
   1,779.89x = 2,150,024.69
5. Step 5: Solve for x
   x = 2,150,024.69/1,779.89
6. Step 6: Final answer
   x = 1,207.95