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Finding the Fourth Proportional to 665.42, 997.40 and 275.21

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Solution

The fourth proportional to 665.42, 997.40 and 275.21 is: 412.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.42 : 997.40 = 275.21 : x
  2. Step 2: Convert to fraction form
    665.42/997.40 = 275.21/x
  3. Step 3: Cross multiply
    665.42x = 997.40 × 275.21
  4. Step 4: Simplify right side
    665.42x = 274,489.96
  5. Step 5: Solve for x
    x = 274,489.96/665.42
  6. Step 6: Final answer
    x = 412.51

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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.