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Finding the Fourth Proportional to 659.79, 910.31 and 397.76

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Solution

The fourth proportional to 659.79, 910.31 and 397.76 is: 548.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.79 : 910.31 = 397.76 : x
  2. Step 2: Convert to fraction form
    659.79/910.31 = 397.76/x
  3. Step 3: Cross multiply
    659.79x = 910.31 × 397.76
  4. Step 4: Simplify right side
    659.79x = 362,078.37
  5. Step 5: Solve for x
    x = 362,078.37/659.79
  6. Step 6: Final answer
    x = 548.78

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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.