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Finding the Fourth Proportional to 510.40, 765.70 and 217.90

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Solution

The fourth proportional to 510.40, 765.70 and 217.90 is: 326.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    510.40 : 765.70 = 217.90 : x
  2. Step 2: Convert to fraction form
    510.40/765.70 = 217.90/x
  3. Step 3: Cross multiply
    510.40x = 765.70 × 217.90
  4. Step 4: Simplify right side
    510.40x = 166,846.03
  5. Step 5: Solve for x
    x = 166,846.03/510.40
  6. Step 6: Final answer
    x = 326.89

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.