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Finding the Fourth Proportional to 665.40, 998.04 and 254.28

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Solution

The fourth proportional to 665.40, 998.04 and 254.28 is: 381.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 998.04 = 254.28 : x
  2. Step 2: Convert to fraction form
    665.40/998.04 = 254.28/x
  3. Step 3: Cross multiply
    665.40x = 998.04 × 254.28
  4. Step 4: Simplify right side
    665.40x = 253,781.61
  5. Step 5: Solve for x
    x = 253,781.61/665.40
  6. Step 6: Final answer
    x = 381.40

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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.