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Finding the Fourth Proportional to 412.70, 619.05 and 385.70

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Solution

The fourth proportional to 412.70, 619.05 and 385.70 is: 578.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.70 : 619.05 = 385.70 : x
  2. Step 2: Convert to fraction form
    412.70/619.05 = 385.70/x
  3. Step 3: Cross multiply
    412.70x = 619.05 × 385.70
  4. Step 4: Simplify right side
    412.70x = 238,767.59
  5. Step 5: Solve for x
    x = 238,767.59/412.70
  6. Step 6: Final answer
    x = 578.55

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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.