Finding the Fourth Proportional to 1,258.28, 1,736.34 and 698.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,258.28 : 1,736.34 = 698.72 : x
2. Step 2: Convert to fraction form
   1,258.28/1,736.34 = 698.72/x
3. Step 3: Cross multiply
   1,258.28x = 1,736.34 × 698.72
4. Step 4: Simplify right side
   1,258.28x = 1,213,215.48
5. Step 5: Solve for x
   x = 1,213,215.48/1,258.28
6. Step 6: Final answer
   x = 964.19