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Finding the Fourth Proportional to 640.68, 882.72 and 465.72

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Solution

The fourth proportional to 640.68, 882.72 and 465.72 is: 641.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.68 : 882.72 = 465.72 : x
  2. Step 2: Convert to fraction form
    640.68/882.72 = 465.72/x
  3. Step 3: Cross multiply
    640.68x = 882.72 × 465.72
  4. Step 4: Simplify right side
    640.68x = 411,100.36
  5. Step 5: Solve for x
    x = 411,100.36/640.68
  6. Step 6: Final answer
    x = 641.66

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.