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Finding the Fourth Proportional to 659.24, 909.80 and 393.78

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Solution

The fourth proportional to 659.24, 909.80 and 393.78 is: 543.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.24 : 909.80 = 393.78 : x
  2. Step 2: Convert to fraction form
    659.24/909.80 = 393.78/x
  3. Step 3: Cross multiply
    659.24x = 909.80 × 393.78
  4. Step 4: Simplify right side
    659.24x = 358,261.04
  5. Step 5: Solve for x
    x = 358,261.04/659.24
  6. Step 6: Final answer
    x = 543.45

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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.