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Finding the Fourth Proportional to 485.60, 670.24 and 299.20

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Solution

The fourth proportional to 485.60, 670.24 and 299.20 is: 412.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.60 : 670.24 = 299.20 : x
  2. Step 2: Convert to fraction form
    485.60/670.24 = 299.20/x
  3. Step 3: Cross multiply
    485.60x = 670.24 × 299.20
  4. Step 4: Simplify right side
    485.60x = 200,535.81
  5. Step 5: Solve for x
    x = 200,535.81/485.60
  6. Step 6: Final answer
    x = 412.97

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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.