Finding the Fourth Proportional to 1,175.85, 1,622.70 and 644.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,175.85 : 1,622.70 = 644.72 : x
2. Step 2: Convert to fraction form
   1,175.85/1,622.70 = 644.72/x
3. Step 3: Cross multiply
   1,175.85x = 1,622.70 × 644.72
4. Step 4: Simplify right side
   1,175.85x = 1,046,179.03
5. Step 5: Solve for x
   x = 1,046,179.03/1,175.85
6. Step 6: Final answer
   x = 889.72