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Finding the Third Proportional to 261 and 319

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Solution

The third proportional to 261 and 319 is: 389.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    261 : 319 = 319 : x
  2. Step 2: Convert to fraction form
    261/319 = 319/x
  3. Step 3: Cross multiply
    261x = 319 × 319
  4. Step 4: Simplify right side
    261x = 101,761
  5. Step 5: Solve for x
    x = 101,761/261
  6. Step 6: Final answer
    x = 389.89

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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.