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Finding the Fourth Proportional to 640.65, 960.97 and 409.65

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Solution

The fourth proportional to 640.65, 960.97 and 409.65 is: 614.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.65 : 960.97 = 409.65 : x
  2. Step 2: Convert to fraction form
    640.65/960.97 = 409.65/x
  3. Step 3: Cross multiply
    640.65x = 960.97 × 409.65
  4. Step 4: Simplify right side
    640.65x = 393,661.36
  5. Step 5: Solve for x
    x = 393,661.36/640.65
  6. Step 6: Final answer
    x = 614.47

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.