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Finding the Fourth Proportional to 485.62, 670.10 and 289.09

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Solution

The fourth proportional to 485.62, 670.10 and 289.09 is: 398.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.62 : 670.10 = 289.09 : x
  2. Step 2: Convert to fraction form
    485.62/670.10 = 289.09/x
  3. Step 3: Cross multiply
    485.62x = 670.10 × 289.09
  4. Step 4: Simplify right side
    485.62x = 193,718.01
  5. Step 5: Solve for x
    x = 193,718.01/485.62
  6. Step 6: Final answer
    x = 398.91

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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.