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Finding the Fourth Proportional to 510.40, 704.39 and 289.39

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Solution

The fourth proportional to 510.40, 704.39 and 289.39 is: 399.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    510.40 : 704.39 = 289.39 : x
  2. Step 2: Convert to fraction form
    510.40/704.39 = 289.39/x
  3. Step 3: Cross multiply
    510.40x = 704.39 × 289.39
  4. Step 4: Simplify right side
    510.40x = 203,839.90
  5. Step 5: Solve for x
    x = 203,839.90/510.40
  6. Step 6: Final answer
    x = 399.38

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.