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Finding the Fourth Proportional to 398.60, 549.66 and 389.66

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Solution

The fourth proportional to 398.60, 549.66 and 389.66 is: 537.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.60 : 549.66 = 389.66 : x
  2. Step 2: Convert to fraction form
    398.60/549.66 = 389.66/x
  3. Step 3: Cross multiply
    398.60x = 549.66 × 389.66
  4. Step 4: Simplify right side
    398.60x = 214,180.52
  5. Step 5: Solve for x
    x = 214,180.52/398.60
  6. Step 6: Final answer
    x = 537.33

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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.