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Finding the Fourth Proportional to 398.95, 549.36 and 389.85

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Solution

The fourth proportional to 398.95, 549.36 and 389.85 is: 536.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.95 : 549.36 = 389.85 : x
  2. Step 2: Convert to fraction form
    398.95/549.36 = 389.85/x
  3. Step 3: Cross multiply
    398.95x = 549.36 × 389.85
  4. Step 4: Simplify right side
    398.95x = 214,165.02
  5. Step 5: Solve for x
    x = 214,165.02/398.95
  6. Step 6: Final answer
    x = 536.83

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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.