Finding the Fourth Proportional to 1,188.83, 1,781.52 and 820.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,188.83 : 1,781.52 = 820.69 : x
2. Step 2: Convert to fraction form
   1,188.83/1,781.52 = 820.69/x
3. Step 3: Cross multiply
   1,188.83x = 1,781.52 × 820.69
4. Step 4: Simplify right side
   1,188.83x = 1,462,066.74
5. Step 5: Solve for x
   x = 1,462,066.74/1,188.83
6. Step 6: Final answer
   x = 1,229.84