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Finding the Fourth Proportional to 320.61, 442.81 and 256.95

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Solution

The fourth proportional to 320.61, 442.81 and 256.95 is: 354.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.61 : 442.81 = 256.95 : x
  2. Step 2: Convert to fraction form
    320.61/442.81 = 256.95/x
  3. Step 3: Cross multiply
    320.61x = 442.81 × 256.95
  4. Step 4: Simplify right side
    320.61x = 113,780.03
  5. Step 5: Solve for x
    x = 113,780.03/320.61
  6. Step 6: Final answer
    x = 354.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.