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Finding the Third Proportional to 691 and 900

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Solution

The third proportional to 691 and 900 is: 1,172.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    691 : 900 = 900 : x
  2. Step 2: Convert to fraction form
    691/900 = 900/x
  3. Step 3: Cross multiply
    691x = 900 × 900
  4. Step 4: Simplify right side
    691x = 810,000
  5. Step 5: Solve for x
    x = 810,000/691
  6. Step 6: Final answer
    x = 1,172.21

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Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.