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Finding the Fourth Proportional to 659.32, 909.84 and 397.20

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Solution

The fourth proportional to 659.32, 909.84 and 397.20 is: 548.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.32 : 909.84 = 397.20 : x
  2. Step 2: Convert to fraction form
    659.32/909.84 = 397.20/x
  3. Step 3: Cross multiply
    659.32x = 909.84 × 397.20
  4. Step 4: Simplify right side
    659.32x = 361,388.45
  5. Step 5: Solve for x
    x = 361,388.45/659.32
  6. Step 6: Final answer
    x = 548.12

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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.