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Finding the Fourth Proportional to 639.58, 881.28 and 606.64

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Solution

The fourth proportional to 639.58, 881.28 and 606.64 is: 835.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.58 : 881.28 = 606.64 : x
  2. Step 2: Convert to fraction form
    639.58/881.28 = 606.64/x
  3. Step 3: Cross multiply
    639.58x = 881.28 × 606.64
  4. Step 4: Simplify right side
    639.58x = 534,619.70
  5. Step 5: Solve for x
    x = 534,619.70/639.58
  6. Step 6: Final answer
    x = 835.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.