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Finding the Fourth Proportional to 659.67, 989.70 and 415.86

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Solution

The fourth proportional to 659.67, 989.70 and 415.86 is: 623.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.67 : 989.70 = 415.86 : x
  2. Step 2: Convert to fraction form
    659.67/989.70 = 415.86/x
  3. Step 3: Cross multiply
    659.67x = 989.70 × 415.86
  4. Step 4: Simplify right side
    659.67x = 411,576.64
  5. Step 5: Solve for x
    x = 411,576.64/659.67
  6. Step 6: Final answer
    x = 623.91

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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.