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Finding the Third Proportional to 218 and 380

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Solution

The third proportional to 218 and 380 is: 662.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    218 : 380 = 380 : x
  2. Step 2: Convert to fraction form
    218/380 = 380/x
  3. Step 3: Cross multiply
    218x = 380 × 380
  4. Step 4: Simplify right side
    218x = 144,400
  5. Step 5: Solve for x
    x = 144,400/218
  6. Step 6: Final answer
    x = 662.39

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These problems maintain the same ratio (1.74) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.