Finding the Fourth Proportional to 1,275.40, 1,760.06 and 715.98

Step by Step Solution

1. Step 1: Write the proportion equation
   1,275.40 : 1,760.06 = 715.98 : x
2. Step 2: Convert to fraction form
   1,275.40/1,760.06 = 715.98/x
3. Step 3: Cross multiply
   1,275.40x = 1,760.06 × 715.98
4. Step 4: Simplify right side
   1,275.40x = 1,260,167.76
5. Step 5: Solve for x
   x = 1,260,167.76/1,275.40
6. Step 6: Final answer
   x = 988.06