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Finding the Fourth Proportional to 390.28, 585.24 and 214.46

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Solution

The fourth proportional to 390.28, 585.24 and 214.46 is: 321.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.28 : 585.24 = 214.46 : x
  2. Step 2: Convert to fraction form
    390.28/585.24 = 214.46/x
  3. Step 3: Cross multiply
    390.28x = 585.24 × 214.46
  4. Step 4: Simplify right side
    390.28x = 125,512.84
  5. Step 5: Solve for x
    x = 125,512.84/390.28
  6. Step 6: Final answer
    x = 321.60

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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.