Finding the Fourth Proportional to 1,258.39, 1,736.57 and 698.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,258.39 : 1,736.57 = 698.86 : x
2. Step 2: Convert to fraction form
   1,258.39/1,736.57 = 698.86/x
3. Step 3: Cross multiply
   1,258.39x = 1,736.57 × 698.86
4. Step 4: Simplify right side
   1,258.39x = 1,213,616.72
5. Step 5: Solve for x
   x = 1,213,616.72/1,258.39
6. Step 6: Final answer
   x = 964.42