Finding the Fourth Proportional to 1,307.40, 1,960.56 and 690.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,307.40 : 1,960.56 = 690.72 : x
2. Step 2: Convert to fraction form
   1,307.40/1,960.56 = 690.72/x
3. Step 3: Cross multiply
   1,307.40x = 1,960.56 × 690.72
4. Step 4: Simplify right side
   1,307.40x = 1,354,198.00
5. Step 5: Solve for x
   x = 1,354,198.00/1,307.40
6. Step 6: Final answer
   x = 1,035.79