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Finding the Fourth Proportional to 388.56, 579.39 and 345.48

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Solution

The fourth proportional to 388.56, 579.39 and 345.48 is: 515.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.56 : 579.39 = 345.48 : x
  2. Step 2: Convert to fraction form
    388.56/579.39 = 345.48/x
  3. Step 3: Cross multiply
    388.56x = 579.39 × 345.48
  4. Step 4: Simplify right side
    388.56x = 200,167.66
  5. Step 5: Solve for x
    x = 200,167.66/388.56
  6. Step 6: Final answer
    x = 515.15

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.