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Finding the Fourth Proportional to 665.19, 997.79 and 639.27

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Solution

The fourth proportional to 665.19, 997.79 and 639.27 is: 958.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.19 : 997.79 = 639.27 : x
  2. Step 2: Convert to fraction form
    665.19/997.79 = 639.27/x
  3. Step 3: Cross multiply
    665.19x = 997.79 × 639.27
  4. Step 4: Simplify right side
    665.19x = 637,854.02
  5. Step 5: Solve for x
    x = 637,854.02/665.19
  6. Step 6: Final answer
    x = 958.91

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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.