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Finding the Fourth Proportional to 645.20, 965.75 and 461.70

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Solution

The fourth proportional to 645.20, 965.75 and 461.70 is: 691.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.20 : 965.75 = 461.70 : x
  2. Step 2: Convert to fraction form
    645.20/965.75 = 461.70/x
  3. Step 3: Cross multiply
    645.20x = 965.75 × 461.70
  4. Step 4: Simplify right side
    645.20x = 445,880.84
  5. Step 5: Solve for x
    x = 445,880.84/645.20
  6. Step 6: Final answer
    x = 691.08

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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.