Finding the Fourth Proportional to 1,290.03, 1,779.61 and 765.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.03 : 1,779.61 = 765.69 : x
2. Step 2: Convert to fraction form
   1,290.03/1,779.61 = 765.69/x
3. Step 3: Cross multiply
   1,290.03x = 1,779.61 × 765.69
4. Step 4: Simplify right side
   1,290.03x = 1,362,629.58
5. Step 5: Solve for x
   x = 1,362,629.58/1,290.03
6. Step 6: Final answer
   x = 1,056.28