Finding the Fourth Proportional to 1,619.89, 2,235.40 and 921.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,619.89 : 2,235.40 = 921.25 : x
2. Step 2: Convert to fraction form
   1,619.89/2,235.40 = 921.25/x
3. Step 3: Cross multiply
   1,619.89x = 2,235.40 × 921.25
4. Step 4: Simplify right side
   1,619.89x = 2,059,362.25
5. Step 5: Solve for x
   x = 2,059,362.25/1,619.89
6. Step 6: Final answer
   x = 1,271.30