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Finding the Third Proportional to 305 and 418

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Solution

The third proportional to 305 and 418 is: 572.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    305 : 418 = 418 : x
  2. Step 2: Convert to fraction form
    305/418 = 418/x
  3. Step 3: Cross multiply
    305x = 418 × 418
  4. Step 4: Simplify right side
    305x = 174,724
  5. Step 5: Solve for x
    x = 174,724/305
  6. Step 6: Final answer
    x = 572.87

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These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.