Finding the Fourth Proportional to 1,158.15, 1,598.28 and 715.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.15 : 1,598.28 = 715.89 : x
2. Step 2: Convert to fraction form
   1,158.15/1,598.28 = 715.89/x
3. Step 3: Cross multiply
   1,158.15x = 1,598.28 × 715.89
4. Step 4: Simplify right side
   1,158.15x = 1,144,192.67
5. Step 5: Solve for x
   x = 1,144,192.67/1,158.15
6. Step 6: Final answer
   x = 987.95