Finding the Fourth Proportional to 1,902.39, 2,855.39 and 978.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,902.39 : 2,855.39 = 978.60 : x
2. Step 2: Convert to fraction form
   1,902.39/2,855.39 = 978.60/x
3. Step 3: Cross multiply
   1,902.39x = 2,855.39 × 978.60
4. Step 4: Simplify right side
   1,902.39x = 2,794,279.76
5. Step 5: Solve for x
   x = 2,794,279.76/1,902.39
6. Step 6: Final answer
   x = 1,468.83