Finding the Fourth Proportional to 1,620.89, 2,236.78 and 922.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,620.89 : 2,236.78 = 922.25 : x
2. Step 2: Convert to fraction form
   1,620.89/2,236.78 = 922.25/x
3. Step 3: Cross multiply
   1,620.89x = 2,236.78 × 922.25
4. Step 4: Simplify right side
   1,620.89x = 2,062,870.36
5. Step 5: Solve for x
   x = 2,062,870.36/1,620.89
6. Step 6: Final answer
   x = 1,272.68