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Finding the Fourth Proportional to 319.87, 480.07 and 256.15

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Solution

The fourth proportional to 319.87, 480.07 and 256.15 is: 384.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.87 : 480.07 = 256.15 : x
  2. Step 2: Convert to fraction form
    319.87/480.07 = 256.15/x
  3. Step 3: Cross multiply
    319.87x = 480.07 × 256.15
  4. Step 4: Simplify right side
    319.87x = 122,967.53
  5. Step 5: Solve for x
    x = 122,967.53/319.87
  6. Step 6: Final answer
    x = 384.44

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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.