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Finding the Fourth Proportional to 486.21, 670.79 and 276.30

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Solution

The fourth proportional to 486.21, 670.79 and 276.30 is: 381.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.21 : 670.79 = 276.30 : x
  2. Step 2: Convert to fraction form
    486.21/670.79 = 276.30/x
  3. Step 3: Cross multiply
    486.21x = 670.79 × 276.30
  4. Step 4: Simplify right side
    486.21x = 185,337.90
  5. Step 5: Solve for x
    x = 185,337.90/486.21
  6. Step 6: Final answer
    x = 381.19

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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.