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Finding the Fourth Proportional to 398.19, 597.65 and 215.72

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Solution

The fourth proportional to 398.19, 597.65 and 215.72 is: 323.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.19 : 597.65 = 215.72 : x
  2. Step 2: Convert to fraction form
    398.19/597.65 = 215.72/x
  3. Step 3: Cross multiply
    398.19x = 597.65 × 215.72
  4. Step 4: Simplify right side
    398.19x = 128,925.06
  5. Step 5: Solve for x
    x = 128,925.06/398.19
  6. Step 6: Final answer
    x = 323.78

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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.