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Finding the Fourth Proportional to 398.82, 549.48 and 380.30

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Solution

The fourth proportional to 398.82, 549.48 and 380.30 is: 523.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.82 : 549.48 = 380.30 : x
  2. Step 2: Convert to fraction form
    398.82/549.48 = 380.30/x
  3. Step 3: Cross multiply
    398.82x = 549.48 × 380.30
  4. Step 4: Simplify right side
    398.82x = 208,965.92
  5. Step 5: Solve for x
    x = 208,965.92/398.82
  6. Step 6: Final answer
    x = 523.96

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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.