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Finding the Fourth Proportional to 485.81, 670.33 and 299.30

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Solution

The fourth proportional to 485.81, 670.33 and 299.30 is: 412.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.81 : 670.33 = 299.30 : x
  2. Step 2: Convert to fraction form
    485.81/670.33 = 299.30/x
  3. Step 3: Cross multiply
    485.81x = 670.33 × 299.30
  4. Step 4: Simplify right side
    485.81x = 200,630.70
  5. Step 5: Solve for x
    x = 200,630.70/485.81
  6. Step 6: Final answer
    x = 412.99

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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.