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Finding the Fourth Proportional to 659.78, 990.23 and 347.64

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Solution

The fourth proportional to 659.78, 990.23 and 347.64 is: 521.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.78 : 990.23 = 347.64 : x
  2. Step 2: Convert to fraction form
    659.78/990.23 = 347.64/x
  3. Step 3: Cross multiply
    659.78x = 990.23 × 347.64
  4. Step 4: Simplify right side
    659.78x = 344,241.82
  5. Step 5: Solve for x
    x = 344,241.82/659.78
  6. Step 6: Final answer
    x = 521.76

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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.