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Finding the Fourth Proportional to 640.58, 959.00 and 487.12

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Solution

The fourth proportional to 640.58, 959.00 and 487.12 is: 729.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.58 : 959.00 = 487.12 : x
  2. Step 2: Convert to fraction form
    640.58/959.00 = 487.12/x
  3. Step 3: Cross multiply
    640.58x = 959.00 × 487.12
  4. Step 4: Simplify right side
    640.58x = 467,143.25
  5. Step 5: Solve for x
    x = 467,143.25/640.58
  6. Step 6: Final answer
    x = 729.25

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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.