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Finding the Fourth Proportional to 809.70, 1,212.90 and 424.14

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Solution

The fourth proportional to 809.70, 1,212.90 and 424.14 is: 635.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.70 : 1,212.90 = 424.14 : x
  2. Step 2: Convert to fraction form
    809.70/1,212.90 = 424.14/x
  3. Step 3: Cross multiply
    809.70x = 1,212.90 × 424.14
  4. Step 4: Simplify right side
    809.70x = 514,439.41
  5. Step 5: Solve for x
    x = 514,439.41/809.70
  6. Step 6: Final answer
    x = 635.35

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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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.