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Finding the Fourth Proportional to 486.21, 671.03 and 289.72

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Solution

The fourth proportional to 486.21, 671.03 and 289.72 is: 399.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.21 : 671.03 = 289.72 : x
  2. Step 2: Convert to fraction form
    486.21/671.03 = 289.72/x
  3. Step 3: Cross multiply
    486.21x = 671.03 × 289.72
  4. Step 4: Simplify right side
    486.21x = 194,410.81
  5. Step 5: Solve for x
    x = 194,410.81/486.21
  6. Step 6: Final answer
    x = 399.85

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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.