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Finding the Fourth Proportional to 319.51, 479.39 and 258.38

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Solution

The fourth proportional to 319.51, 479.39 and 258.38 is: 387.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.51 : 479.39 = 258.38 : x
  2. Step 2: Convert to fraction form
    319.51/479.39 = 258.38/x
  3. Step 3: Cross multiply
    319.51x = 479.39 × 258.38
  4. Step 4: Simplify right side
    319.51x = 123,863.62
  5. Step 5: Solve for x
    x = 123,863.62/319.51
  6. Step 6: Final answer
    x = 387.67

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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.