Finding the Fourth Proportional to 1,903.77, 2,855.61 and 978.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,903.77 : 2,855.61 = 978.78 : x
2. Step 2: Convert to fraction form
   1,903.77/2,855.61 = 978.78/x
3. Step 3: Cross multiply
   1,903.77x = 2,855.61 × 978.78
4. Step 4: Simplify right side
   1,903.77x = 2,795,013.96
5. Step 5: Solve for x
   x = 2,795,013.96/1,903.77
6. Step 6: Final answer
   x = 1,468.15