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Finding the Fourth Proportional to 640.29, 959.72 and 315.89

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Solution

The fourth proportional to 640.29, 959.72 and 315.89 is: 473.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.29 : 959.72 = 315.89 : x
  2. Step 2: Convert to fraction form
    640.29/959.72 = 315.89/x
  3. Step 3: Cross multiply
    640.29x = 959.72 × 315.89
  4. Step 4: Simplify right side
    640.29x = 303,159.57
  5. Step 5: Solve for x
    x = 303,159.57/640.29
  6. Step 6: Final answer
    x = 473.47

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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.