Finding the Fourth Proportional to 1,642.62, 2,266.13 and 978.83

Step by Step Solution

1. Step 1: Write the proportion equation
   1,642.62 : 2,266.13 = 978.83 : x
2. Step 2: Convert to fraction form
   1,642.62/2,266.13 = 978.83/x
3. Step 3: Cross multiply
   1,642.62x = 2,266.13 × 978.83
4. Step 4: Simplify right side
   1,642.62x = 2,218,139.80
5. Step 5: Solve for x
   x = 2,218,139.80/1,642.62
6. Step 6: Final answer
   x = 1,350.37