Finding the Fourth Proportional to 1,216.72, 1,678.46 and 719.18

Step by Step Solution

1. Step 1: Write the proportion equation
   1,216.72 : 1,678.46 = 719.18 : x
2. Step 2: Convert to fraction form
   1,216.72/1,678.46 = 719.18/x
3. Step 3: Cross multiply
   1,216.72x = 1,678.46 × 719.18
4. Step 4: Simplify right side
   1,216.72x = 1,207,114.86
5. Step 5: Solve for x
   x = 1,207,114.86/1,216.72
6. Step 6: Final answer
   x = 992.11