Finding the Fourth Proportional to 1,222.64, 1,832.52 and 644.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,222.64 : 1,832.52 = 644.72 : x
2. Step 2: Convert to fraction form
   1,222.64/1,832.52 = 644.72/x
3. Step 3: Cross multiply
   1,222.64x = 1,832.52 × 644.72
4. Step 4: Simplify right side
   1,222.64x = 1,181,462.29
5. Step 5: Solve for x
   x = 1,181,462.29/1,222.64
6. Step 6: Final answer
   x = 966.32