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Finding the Fourth Proportional to 320.23, 442.68 and 287.42

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Solution

The fourth proportional to 320.23, 442.68 and 287.42 is: 397.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.23 : 442.68 = 287.42 : x
  2. Step 2: Convert to fraction form
    320.23/442.68 = 287.42/x
  3. Step 3: Cross multiply
    320.23x = 442.68 × 287.42
  4. Step 4: Simplify right side
    320.23x = 127,235.09
  5. Step 5: Solve for x
    x = 127,235.09/320.23
  6. Step 6: Final answer
    x = 397.32

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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.