Finding the Fourth Proportional to 2,451.72, 3,678.18 and 808.20

Step by Step Solution

1. Step 1: Write the proportion equation
   2,451.72 : 3,678.18 = 808.20 : x
2. Step 2: Convert to fraction form
   2,451.72/3,678.18 = 808.20/x
3. Step 3: Cross multiply
   2,451.72x = 3,678.18 × 808.20
4. Step 4: Simplify right side
   2,451.72x = 2,972,705.08
5. Step 5: Solve for x
   x = 2,972,705.08/2,451.72
6. Step 6: Final answer
   x = 1,212.50