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Finding the Fourth Proportional to 320.86, 442.71 and 279.35

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Solution

The fourth proportional to 320.86, 442.71 and 279.35 is: 385.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.86 : 442.71 = 279.35 : x
  2. Step 2: Convert to fraction form
    320.86/442.71 = 279.35/x
  3. Step 3: Cross multiply
    320.86x = 442.71 × 279.35
  4. Step 4: Simplify right side
    320.86x = 123,671.04
  5. Step 5: Solve for x
    x = 123,671.04/320.86
  6. Step 6: Final answer
    x = 385.44

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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.