Finding the Fourth Proportional to 1,502.75, 2,073.90 and 978.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,502.75 : 2,073.90 = 978.78 : x
2. Step 2: Convert to fraction form
   1,502.75/2,073.90 = 978.78/x
3. Step 3: Cross multiply
   1,502.75x = 2,073.90 × 978.78
4. Step 4: Simplify right side
   1,502.75x = 2,029,903.29
5. Step 5: Solve for x
   x = 2,029,903.29/1,502.75
6. Step 6: Final answer
   x = 1,350.79