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Finding the Third Proportional to 255 and 400

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Solution

The third proportional to 255 and 400 is: 627.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    255 : 400 = 400 : x
  2. Step 2: Convert to fraction form
    255/400 = 400/x
  3. Step 3: Cross multiply
    255x = 400 × 400
  4. Step 4: Simplify right side
    255x = 160,000
  5. Step 5: Solve for x
    x = 160,000/255
  6. Step 6: Final answer
    x = 627.45

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Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.