Finding the Fourth Proportional to 2,144.81, 3,216.69 and 828.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,144.81 : 3,216.69 = 828.12 : x
2. Step 2: Convert to fraction form
   2,144.81/3,216.69 = 828.12/x
3. Step 3: Cross multiply
   2,144.81x = 3,216.69 × 828.12
4. Step 4: Simplify right side
   2,144.81x = 2,663,805.32
5. Step 5: Solve for x
   x = 2,663,805.32/2,144.81
6. Step 6: Final answer
   x = 1,241.98