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Finding the Fourth Proportional to 319.39, 479.12 and 136.80

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Solution

The fourth proportional to 319.39, 479.12 and 136.80 is: 205.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.39 : 479.12 = 136.80 : x
  2. Step 2: Convert to fraction form
    319.39/479.12 = 136.80/x
  3. Step 3: Cross multiply
    319.39x = 479.12 × 136.80
  4. Step 4: Simplify right side
    319.39x = 65,543.96
  5. Step 5: Solve for x
    x = 65,543.96/319.39
  6. Step 6: Final answer
    x = 205.22

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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.