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Finding the Third Proportional to 405 and 624

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Solution

The third proportional to 405 and 624 is: 961.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    405 : 624 = 624 : x
  2. Step 2: Convert to fraction form
    405/624 = 624/x
  3. Step 3: Cross multiply
    405x = 624 × 624
  4. Step 4: Simplify right side
    405x = 389,376
  5. Step 5: Solve for x
    x = 389,376/405
  6. Step 6: Final answer
    x = 961.42

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Why These Related Problems?

These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.