Finding the Fourth Proportional to 1,298.87, 1,792.42 and 709.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,298.87 : 1,792.42 = 709.39 : x
2. Step 2: Convert to fraction form
   1,298.87/1,792.42 = 709.39/x
3. Step 3: Cross multiply
   1,298.87x = 1,792.42 × 709.39
4. Step 4: Simplify right side
   1,298.87x = 1,271,515.86
5. Step 5: Solve for x
   x = 1,271,515.86/1,298.87
6. Step 6: Final answer
   x = 978.94