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Finding the Fourth Proportional to 613.70, 920.55 and 512.90

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Solution

The fourth proportional to 613.70, 920.55 and 512.90 is: 769.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.70 : 920.55 = 512.90 : x
  2. Step 2: Convert to fraction form
    613.70/920.55 = 512.90/x
  3. Step 3: Cross multiply
    613.70x = 920.55 × 512.90
  4. Step 4: Simplify right side
    613.70x = 472,150.10
  5. Step 5: Solve for x
    x = 472,150.10/613.70
  6. Step 6: Final answer
    x = 769.35

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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.