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Finding the Fourth Proportional to 640.28, 958.66 and 485.76

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Solution

The fourth proportional to 640.28, 958.66 and 485.76 is: 727.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.28 : 958.66 = 485.76 : x
  2. Step 2: Convert to fraction form
    640.28/958.66 = 485.76/x
  3. Step 3: Cross multiply
    640.28x = 958.66 × 485.76
  4. Step 4: Simplify right side
    640.28x = 465,678.68
  5. Step 5: Solve for x
    x = 465,678.68/640.28
  6. Step 6: Final answer
    x = 727.30

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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.