Finding the Fourth Proportional to 1,280.67, 1,920.72 and 622.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,280.67 : 1,920.72 = 622.53 : x
2. Step 2: Convert to fraction form
   1,280.67/1,920.72 = 622.53/x
3. Step 3: Cross multiply
   1,280.67x = 1,920.72 × 622.53
4. Step 4: Simplify right side
   1,280.67x = 1,195,705.82
5. Step 5: Solve for x
   x = 1,195,705.82/1,280.67
6. Step 6: Final answer
   x = 933.66