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Finding the Third Proportional to 215 and 378

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Solution

The third proportional to 215 and 378 is: 664.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    215 : 378 = 378 : x
  2. Step 2: Convert to fraction form
    215/378 = 378/x
  3. Step 3: Cross multiply
    215x = 378 × 378
  4. Step 4: Simplify right side
    215x = 142,884
  5. Step 5: Solve for x
    x = 142,884/215
  6. Step 6: Final answer
    x = 664.58

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These problems maintain the same ratio (1.76) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.