Finding the Fourth Proportional to 1,158.20, 1,597.86 and 715.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.20 : 1,597.86 = 715.88 : x
2. Step 2: Convert to fraction form
   1,158.20/1,597.86 = 715.88/x
3. Step 3: Cross multiply
   1,158.20x = 1,597.86 × 715.88
4. Step 4: Simplify right side
   1,158.20x = 1,143,876.02
5. Step 5: Solve for x
   x = 1,143,876.02/1,158.20
6. Step 6: Final answer
   x = 987.63