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Finding the Fourth Proportional to 665.45, 998.39 and 402.20

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Solution

The fourth proportional to 665.45, 998.39 and 402.20 is: 603.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.45 : 998.39 = 402.20 : x
  2. Step 2: Convert to fraction form
    665.45/998.39 = 402.20/x
  3. Step 3: Cross multiply
    665.45x = 998.39 × 402.20
  4. Step 4: Simplify right side
    665.45x = 401,552.46
  5. Step 5: Solve for x
    x = 401,552.46/665.45
  6. Step 6: Final answer
    x = 603.43

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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.