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Finding the Third Proportional to 620 and 905

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Solution

The third proportional to 620 and 905 is: 1,321.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    620 : 905 = 905 : x
  2. Step 2: Convert to fraction form
    620/905 = 905/x
  3. Step 3: Cross multiply
    620x = 905 × 905
  4. Step 4: Simplify right side
    620x = 819,025
  5. Step 5: Solve for x
    x = 819,025/620
  6. Step 6: Final answer
    x = 1,321.01

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Why These Related Problems?

These problems maintain the same ratio (1.46) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.