Finding the Fourth Proportional to 1,290.86, 1,782.24 and 767.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.86 : 1,782.24 = 767.06 : x
2. Step 2: Convert to fraction form
   1,290.86/1,782.24 = 767.06/x
3. Step 3: Cross multiply
   1,290.86x = 1,782.24 × 767.06
4. Step 4: Simplify right side
   1,290.86x = 1,367,085.01
5. Step 5: Solve for x
   x = 1,367,085.01/1,290.86
6. Step 6: Final answer
   x = 1,059.05