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Finding the Fourth Proportional to 645.77, 968.66 and 280.56

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Solution

The fourth proportional to 645.77, 968.66 and 280.56 is: 420.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.77 : 968.66 = 280.56 : x
  2. Step 2: Convert to fraction form
    645.77/968.66 = 280.56/x
  3. Step 3: Cross multiply
    645.77x = 968.66 × 280.56
  4. Step 4: Simplify right side
    645.77x = 271,770.53
  5. Step 5: Solve for x
    x = 271,770.53/645.77
  6. Step 6: Final answer
    x = 420.85

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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.