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Finding the Fourth Proportional to 665.00, 909.15 and 639.48

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Solution

The fourth proportional to 665.00, 909.15 and 639.48 is: 874.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.00 : 909.15 = 639.48 : x
  2. Step 2: Convert to fraction form
    665.00/909.15 = 639.48/x
  3. Step 3: Cross multiply
    665.00x = 909.15 × 639.48
  4. Step 4: Simplify right side
    665.00x = 581,383.24
  5. Step 5: Solve for x
    x = 581,383.24/665.00
  6. Step 6: Final answer
    x = 874.27

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.