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Finding the Fourth Proportional to 643.38, 887.66 and 456.72

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Solution

The fourth proportional to 643.38, 887.66 and 456.72 is: 630.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.38 : 887.66 = 456.72 : x
  2. Step 2: Convert to fraction form
    643.38/887.66 = 456.72/x
  3. Step 3: Cross multiply
    643.38x = 887.66 × 456.72
  4. Step 4: Simplify right side
    643.38x = 405,412.08
  5. Step 5: Solve for x
    x = 405,412.08/643.38
  6. Step 6: Final answer
    x = 630.13

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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.