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Finding the Third Proportional to 210 and 391.50

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Solution

The third proportional to 210 and 391.50 is: 729.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    210 : 391.50 = 391.50 : x
  2. Step 2: Convert to fraction form
    210/391.50 = 391.50/x
  3. Step 3: Cross multiply
    210x = 391.50 × 391.50
  4. Step 4: Simplify right side
    210x = 153,272.25
  5. Step 5: Solve for x
    x = 153,272.25/210
  6. Step 6: Final answer
    x = 729.87

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Why These Related Problems?

These problems maintain the same ratio (1.86) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.