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Finding the Fourth Proportional to 809.49, 1,214.09 and 398.49

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Solution

The fourth proportional to 809.49, 1,214.09 and 398.49 is: 597.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.49 : 1,214.09 = 398.49 : x
  2. Step 2: Convert to fraction form
    809.49/1,214.09 = 398.49/x
  3. Step 3: Cross multiply
    809.49x = 1,214.09 × 398.49
  4. Step 4: Simplify right side
    809.49x = 483,797.67
  5. Step 5: Solve for x
    x = 483,797.67/809.49
  6. Step 6: Final answer
    x = 597.65

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Half scale
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Double scale
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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.