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Finding the Fourth Proportional to 319.20, 478.56 and 254.88

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Solution

The fourth proportional to 319.20, 478.56 and 254.88 is: 382.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.20 : 478.56 = 254.88 : x
  2. Step 2: Convert to fraction form
    319.20/478.56 = 254.88/x
  3. Step 3: Cross multiply
    319.20x = 478.56 × 254.88
  4. Step 4: Simplify right side
    319.20x = 121,975.37
  5. Step 5: Solve for x
    x = 121,975.37/319.20
  6. Step 6: Final answer
    x = 382.13

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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.