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Finding the Fourth Proportional to 659.48, 988.89 and 385.65

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Solution

The fourth proportional to 659.48, 988.89 and 385.65 is: 578.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.48 : 988.89 = 385.65 : x
  2. Step 2: Convert to fraction form
    659.48/988.89 = 385.65/x
  3. Step 3: Cross multiply
    659.48x = 988.89 × 385.65
  4. Step 4: Simplify right side
    659.48x = 381,365.43
  5. Step 5: Solve for x
    x = 381,365.43/659.48
  6. Step 6: Final answer
    x = 578.29

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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.