Finding the Fourth Proportional to 1,065.48, 1,470.16 and 645.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,065.48 : 1,470.16 = 645.72 : x
2. Step 2: Convert to fraction form
   1,065.48/1,470.16 = 645.72/x
3. Step 3: Cross multiply
   1,065.48x = 1,470.16 × 645.72
4. Step 4: Simplify right side
   1,065.48x = 949,311.72
5. Step 5: Solve for x
   x = 949,311.72/1,065.48
6. Step 6: Final answer
   x = 890.97