Finding the Fourth Proportional to 1,157.48, 1,597.60 and 715.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,157.48 : 1,597.60 = 715.72 : x
2. Step 2: Convert to fraction form
   1,157.48/1,597.60 = 715.72/x
3. Step 3: Cross multiply
   1,157.48x = 1,597.60 × 715.72
4. Step 4: Simplify right side
   1,157.48x = 1,143,434.27
5. Step 5: Solve for x
   x = 1,143,434.27/1,157.48
6. Step 6: Final answer
   x = 987.87