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Finding the Fourth Proportional to 643.98, 966.01 and 221.65

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Solution

The fourth proportional to 643.98, 966.01 and 221.65 is: 332.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.98 : 966.01 = 221.65 : x
  2. Step 2: Convert to fraction form
    643.98/966.01 = 221.65/x
  3. Step 3: Cross multiply
    643.98x = 966.01 × 221.65
  4. Step 4: Simplify right side
    643.98x = 214,116.12
  5. Step 5: Solve for x
    x = 214,116.12/643.98
  6. Step 6: Final answer
    x = 332.49

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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.