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Finding the Third Proportional to 388 and 400

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Solution

The third proportional to 388 and 400 is: 412.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    388 : 400 = 400 : x
  2. Step 2: Convert to fraction form
    388/400 = 400/x
  3. Step 3: Cross multiply
    388x = 400 × 400
  4. Step 4: Simplify right side
    388x = 160,000
  5. Step 5: Solve for x
    x = 160,000/388
  6. Step 6: Final answer
    x = 412.37

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These problems maintain the same ratio (1.03) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.