Finding the Fourth Proportional to 1,145.46, 1,716.72 and 870.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,145.46 : 1,716.72 = 870.72 : x
2. Step 2: Convert to fraction form
   1,145.46/1,716.72 = 870.72/x
3. Step 3: Cross multiply
   1,145.46x = 1,716.72 × 870.72
4. Step 4: Simplify right side
   1,145.46x = 1,494,782.44
5. Step 5: Solve for x
   x = 1,494,782.44/1,145.46
6. Step 6: Final answer
   x = 1,304.96