Finding the Fourth Proportional to 1,502.90, 2,073.98 and 839.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,502.90 : 2,073.98 = 839.78 : x
2. Step 2: Convert to fraction form
   1,502.90/2,073.98 = 839.78/x
3. Step 3: Cross multiply
   1,502.90x = 2,073.98 × 839.78
4. Step 4: Simplify right side
   1,502.90x = 1,741,682.73
5. Step 5: Solve for x
   x = 1,741,682.73/1,502.90
6. Step 6: Final answer
   x = 1,158.88