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Finding the Fourth Proportional to 645.40, 968.10 and 621.10

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Solution

The fourth proportional to 645.40, 968.10 and 621.10 is: 931.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.40 : 968.10 = 621.10 : x
  2. Step 2: Convert to fraction form
    645.40/968.10 = 621.10/x
  3. Step 3: Cross multiply
    645.40x = 968.10 × 621.10
  4. Step 4: Simplify right side
    645.40x = 601,286.91
  5. Step 5: Solve for x
    x = 601,286.91/645.40
  6. Step 6: Final answer
    x = 931.65

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Half scale
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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.