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Finding the Fourth Proportional to 320.85, 442.56 and 208.77

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Solution

The fourth proportional to 320.85, 442.56 and 208.77 is: 287.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.85 : 442.56 = 208.77 : x
  2. Step 2: Convert to fraction form
    320.85/442.56 = 208.77/x
  3. Step 3: Cross multiply
    320.85x = 442.56 × 208.77
  4. Step 4: Simplify right side
    320.85x = 92,393.25
  5. Step 5: Solve for x
    x = 92,393.25/320.85
  6. Step 6: Final answer
    x = 287.96

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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.