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Finding the Third Proportional to 515 and 630

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Solution

The third proportional to 515 and 630 is: 770.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    515 : 630 = 630 : x
  2. Step 2: Convert to fraction form
    515/630 = 630/x
  3. Step 3: Cross multiply
    515x = 630 × 630
  4. Step 4: Simplify right side
    515x = 396,900
  5. Step 5: Solve for x
    x = 396,900/515
  6. Step 6: Final answer
    x = 770.68

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Why These Related Problems?

These problems maintain the same ratio (1.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.