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Finding the Third Proportional to 820 and 900

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Solution

The third proportional to 820 and 900 is: 987.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    820 : 900 = 900 : x
  2. Step 2: Convert to fraction form
    820/900 = 900/x
  3. Step 3: Cross multiply
    820x = 900 × 900
  4. Step 4: Simplify right side
    820x = 810,000
  5. Step 5: Solve for x
    x = 810,000/820
  6. Step 6: Final answer
    x = 987.80

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Why These Related Problems?

These problems maintain the same ratio (1.10) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.