Finding the Fourth Proportional to 1,065.16, 1,469.59 and 645.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,065.16 : 1,469.59 = 645.76 : x
2. Step 2: Convert to fraction form
   1,065.16/1,469.59 = 645.76/x
3. Step 3: Cross multiply
   1,065.16x = 1,469.59 × 645.76
4. Step 4: Simplify right side
   1,065.16x = 949,002.44
5. Step 5: Solve for x
   x = 949,002.44/1,065.16
6. Step 6: Final answer
   x = 890.95