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Finding the Fourth Proportional to 539.64, 809.45 and 385.64

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Solution

The fourth proportional to 539.64, 809.45 and 385.64 is: 578.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.64 : 809.45 = 385.64 : x
  2. Step 2: Convert to fraction form
    539.64/809.45 = 385.64/x
  3. Step 3: Cross multiply
    539.64x = 809.45 × 385.64
  4. Step 4: Simplify right side
    539.64x = 312,156.30
  5. Step 5: Solve for x
    x = 312,156.30/539.64
  6. Step 6: Final answer
    x = 578.45

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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.