Finding the Fourth Proportional to 3,318.50, 4,978.06 and 978.51

Step by Step Solution

1. Step 1: Write the proportion equation
   3,318.50 : 4,978.06 = 978.51 : x
2. Step 2: Convert to fraction form
   3,318.50/4,978.06 = 978.51/x
3. Step 3: Cross multiply
   3,318.50x = 4,978.06 × 978.51
4. Step 4: Simplify right side
   3,318.50x = 4,871,056.60
5. Step 5: Solve for x
   x = 4,871,056.60/3,318.50
6. Step 6: Final answer
   x = 1,467.85