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Finding the Fourth Proportional to 319.32, 479.25 and 285.57

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Solution

The fourth proportional to 319.32, 479.25 and 285.57 is: 428.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.32 : 479.25 = 285.57 : x
  2. Step 2: Convert to fraction form
    319.32/479.25 = 285.57/x
  3. Step 3: Cross multiply
    319.32x = 479.25 × 285.57
  4. Step 4: Simplify right side
    319.32x = 136,859.42
  5. Step 5: Solve for x
    x = 136,859.42/319.32
  6. Step 6: Final answer
    x = 428.60

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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.