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Finding the Third Proportional to 210 and 255

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Solution

The third proportional to 210 and 255 is: 309.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    210 : 255 = 255 : x
  2. Step 2: Convert to fraction form
    210/255 = 255/x
  3. Step 3: Cross multiply
    210x = 255 × 255
  4. Step 4: Simplify right side
    210x = 65,025
  5. Step 5: Solve for x
    x = 65,025/210
  6. Step 6: Final answer
    x = 309.64

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Why These Related Problems?

These problems maintain the same ratio (1.21) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.