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Finding the Fourth Proportional to 388.28, 579.67 and 345.08

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Solution

The fourth proportional to 388.28, 579.67 and 345.08 is: 515.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.28 : 579.67 = 345.08 : x
  2. Step 2: Convert to fraction form
    388.28/579.67 = 345.08/x
  3. Step 3: Cross multiply
    388.28x = 579.67 × 345.08
  4. Step 4: Simplify right side
    388.28x = 200,032.52
  5. Step 5: Solve for x
    x = 200,032.52/388.28
  6. Step 6: Final answer
    x = 515.18

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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.