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Finding the Fourth Proportional to 309.70, 464.55 and 279.30

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Solution

The fourth proportional to 309.70, 464.55 and 279.30 is: 418.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.70 : 464.55 = 279.30 : x
  2. Step 2: Convert to fraction form
    309.70/464.55 = 279.30/x
  3. Step 3: Cross multiply
    309.70x = 464.55 × 279.30
  4. Step 4: Simplify right side
    309.70x = 129,748.82
  5. Step 5: Solve for x
    x = 129,748.82/309.70
  6. Step 6: Final answer
    x = 418.95

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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.