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Finding the Fourth Proportional to 639.23, 959.05 and 485.33

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Solution

The fourth proportional to 639.23, 959.05 and 485.33 is: 728.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.23 : 959.05 = 485.33 : x
  2. Step 2: Convert to fraction form
    639.23/959.05 = 485.33/x
  3. Step 3: Cross multiply
    639.23x = 959.05 × 485.33
  4. Step 4: Simplify right side
    639.23x = 465,455.74
  5. Step 5: Solve for x
    x = 465,455.74/639.23
  6. Step 6: Final answer
    x = 728.15

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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.