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Finding the Fourth Proportional to 640.15, 958.15 and 331.57

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Solution

The fourth proportional to 640.15, 958.15 and 331.57 is: 496.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.15 : 958.15 = 331.57 : x
  2. Step 2: Convert to fraction form
    640.15/958.15 = 331.57/x
  3. Step 3: Cross multiply
    640.15x = 958.15 × 331.57
  4. Step 4: Simplify right side
    640.15x = 317,693.80
  5. Step 5: Solve for x
    x = 317,693.80/640.15
  6. Step 6: Final answer
    x = 496.28

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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.