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Finding the Fourth Proportional to 456.39, 629.45 and 308.79

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Solution

The fourth proportional to 456.39, 629.45 and 308.79 is: 425.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    456.39 : 629.45 = 308.79 : x
  2. Step 2: Convert to fraction form
    456.39/629.45 = 308.79/x
  3. Step 3: Cross multiply
    456.39x = 629.45 × 308.79
  4. Step 4: Simplify right side
    456.39x = 194,366.32
  5. Step 5: Solve for x
    x = 194,366.32/456.39
  6. Step 6: Final answer
    x = 425.88

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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.