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Finding the Fourth Proportional to 645.12, 966.87 and 429.12

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Solution

The fourth proportional to 645.12, 966.87 and 429.12 is: 643.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.12 : 966.87 = 429.12 : x
  2. Step 2: Convert to fraction form
    645.12/966.87 = 429.12/x
  3. Step 3: Cross multiply
    645.12x = 966.87 × 429.12
  4. Step 4: Simplify right side
    645.12x = 414,903.25
  5. Step 5: Solve for x
    x = 414,903.25/645.12
  6. Step 6: Final answer
    x = 643.14

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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.