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Finding the Fourth Proportional to 630.40, 945.60 and 411.70

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Solution

The fourth proportional to 630.40, 945.60 and 411.70 is: 617.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.40 : 945.60 = 411.70 : x
  2. Step 2: Convert to fraction form
    630.40/945.60 = 411.70/x
  3. Step 3: Cross multiply
    630.40x = 945.60 × 411.70
  4. Step 4: Simplify right side
    630.40x = 389,303.52
  5. Step 5: Solve for x
    x = 389,303.52/630.40
  6. Step 6: Final answer
    x = 617.55

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Double scale
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Similar ratio
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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.