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Finding the Fourth Proportional to 645.72, 965.70 and 634.20

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Solution

The fourth proportional to 645.72, 965.70 and 634.20 is: 948.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.72 : 965.70 = 634.20 : x
  2. Step 2: Convert to fraction form
    645.72/965.70 = 634.20/x
  3. Step 3: Cross multiply
    645.72x = 965.70 × 634.20
  4. Step 4: Simplify right side
    645.72x = 612,446.94
  5. Step 5: Solve for x
    x = 612,446.94/645.72
  6. Step 6: Final answer
    x = 948.47

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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.