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Finding the Fourth Proportional to 640.12, 959.56 and 485.60

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Solution

The fourth proportional to 640.12, 959.56 and 485.60 is: 727.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.12 : 959.56 = 485.60 : x
  2. Step 2: Convert to fraction form
    640.12/959.56 = 485.60/x
  3. Step 3: Cross multiply
    640.12x = 959.56 × 485.60
  4. Step 4: Simplify right side
    640.12x = 465,962.34
  5. Step 5: Solve for x
    x = 465,962.34/640.12
  6. Step 6: Final answer
    x = 727.93

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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.