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Finding the Third Proportional to 210 and 380

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Solution

The third proportional to 210 and 380 is: 687.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    210 : 380 = 380 : x
  2. Step 2: Convert to fraction form
    210/380 = 380/x
  3. Step 3: Cross multiply
    210x = 380 × 380
  4. Step 4: Simplify right side
    210x = 144,400
  5. Step 5: Solve for x
    x = 144,400/210
  6. Step 6: Final answer
    x = 687.62

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These problems maintain the same ratio (1.81) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.