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Finding the Fourth Proportional to 659.89, 910.47 and 397.90

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Solution

The fourth proportional to 659.89, 910.47 and 397.90 is: 548.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.89 : 910.47 = 397.90 : x
  2. Step 2: Convert to fraction form
    659.89/910.47 = 397.90/x
  3. Step 3: Cross multiply
    659.89x = 910.47 × 397.90
  4. Step 4: Simplify right side
    659.89x = 362,276.01
  5. Step 5: Solve for x
    x = 362,276.01/659.89
  6. Step 6: Final answer
    x = 548.99

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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.