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Finding the Fourth Proportional to 684.38, 945.68 and 487.55

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Solution

The fourth proportional to 684.38, 945.68 and 487.55 is: 673.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    684.38 : 945.68 = 487.55 : x
  2. Step 2: Convert to fraction form
    684.38/945.68 = 487.55/x
  3. Step 3: Cross multiply
    684.38x = 945.68 × 487.55
  4. Step 4: Simplify right side
    684.38x = 461,066.28
  5. Step 5: Solve for x
    x = 461,066.28/684.38
  6. Step 6: Final answer
    x = 673.70

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Half scale
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Double scale
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Similar ratio
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1.5x scale

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.