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Finding the Fourth Proportional to 398.70, 597.60 and 215.76

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Solution

The fourth proportional to 398.70, 597.60 and 215.76 is: 323.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.70 : 597.60 = 215.76 : x
  2. Step 2: Convert to fraction form
    398.70/597.60 = 215.76/x
  3. Step 3: Cross multiply
    398.70x = 597.60 × 215.76
  4. Step 4: Simplify right side
    398.70x = 128,938.18
  5. Step 5: Solve for x
    x = 128,938.18/398.70
  6. Step 6: Final answer
    x = 323.40

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.