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Finding the Fourth Proportional to 320.70, 442.64 and 208.64

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Solution

The fourth proportional to 320.70, 442.64 and 208.64 is: 287.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.70 : 442.64 = 208.64 : x
  2. Step 2: Convert to fraction form
    320.70/442.64 = 208.64/x
  3. Step 3: Cross multiply
    320.70x = 442.64 × 208.64
  4. Step 4: Simplify right side
    320.70x = 92,352.41
  5. Step 5: Solve for x
    x = 92,352.41/320.70
  6. Step 6: Final answer
    x = 287.97

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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.