Finding the Fourth Proportional to 1,608.02, 2,218.56 and 978.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,608.02 : 2,218.56 = 978.80 : x
2. Step 2: Convert to fraction form
   1,608.02/2,218.56 = 978.80/x
3. Step 3: Cross multiply
   1,608.02x = 2,218.56 × 978.80
4. Step 4: Simplify right side
   1,608.02x = 2,171,526.53
5. Step 5: Solve for x
   x = 2,171,526.53/1,608.02
6. Step 6: Final answer
   x = 1,350.44