Finding the Fourth Proportional to 1,158.36, 1,736.82 and 645.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,158.36 : 1,736.82 = 645.72 : x
2. Step 2: Convert to fraction form
   1,158.36/1,736.82 = 645.72/x
3. Step 3: Cross multiply
   1,158.36x = 1,736.82 × 645.72
4. Step 4: Simplify right side
   1,158.36x = 1,121,499.41
5. Step 5: Solve for x
   x = 1,121,499.41/1,158.36
6. Step 6: Final answer
   x = 968.18