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Finding the Fourth Proportional to 659.05, 987.44 and 427.67

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Solution

The fourth proportional to 659.05, 987.44 and 427.67 is: 640.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.05 : 987.44 = 427.67 : x
  2. Step 2: Convert to fraction form
    659.05/987.44 = 427.67/x
  3. Step 3: Cross multiply
    659.05x = 987.44 × 427.67
  4. Step 4: Simplify right side
    659.05x = 422,295.09
  5. Step 5: Solve for x
    x = 422,295.09/659.05
  6. Step 6: Final answer
    x = 640.77

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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.