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Finding the Fourth Proportional to 665.40, 998.34 and 299.91

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Solution

The fourth proportional to 665.40, 998.34 and 299.91 is: 449.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 998.34 = 299.91 : x
  2. Step 2: Convert to fraction form
    665.40/998.34 = 299.91/x
  3. Step 3: Cross multiply
    665.40x = 998.34 × 299.91
  4. Step 4: Simplify right side
    665.40x = 299,412.15
  5. Step 5: Solve for x
    x = 299,412.15/665.40
  6. Step 6: Final answer
    x = 449.97

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.