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Finding the Third Proportional to 280 and 400

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Solution

The third proportional to 280 and 400 is: 571.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    280 : 400 = 400 : x
  2. Step 2: Convert to fraction form
    280/400 = 400/x
  3. Step 3: Cross multiply
    280x = 400 × 400
  4. Step 4: Simplify right side
    280x = 160,000
  5. Step 5: Solve for x
    x = 160,000/280
  6. Step 6: Final answer
    x = 571.43

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Why These Related Problems?

These problems maintain the same ratio (1.43) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.