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Finding the Third Proportional to 315.09 and 489.89

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Solution

The third proportional to 315.09 and 489.89 is: 761.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.09 : 489.89 = 489.89 : x
  2. Step 2: Convert to fraction form
    315.09/489.89 = 489.89/x
  3. Step 3: Cross multiply
    315.09x = 489.89 × 489.89
  4. Step 4: Simplify right side
    315.09x = 239,992.82
  5. Step 5: Solve for x
    x = 239,992.82/315.09
  6. Step 6: Final answer
    x = 761.66

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.