Finding the Fourth Proportional to 1,569.88, 2,355.18 and 840.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,569.88 : 2,355.18 = 840.16 : x
2. Step 2: Convert to fraction form
   1,569.88/2,355.18 = 840.16/x
3. Step 3: Cross multiply
   1,569.88x = 2,355.18 × 840.16
4. Step 4: Simplify right side
   1,569.88x = 1,978,728.03
5. Step 5: Solve for x
   x = 1,978,728.03/1,569.88
6. Step 6: Final answer
   x = 1,260.43