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Finding the Fourth Proportional to 214.40, 321.12 and 171.20

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Solution

The fourth proportional to 214.40, 321.12 and 171.20 is: 256.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    214.40 : 321.12 = 171.20 : x
  2. Step 2: Convert to fraction form
    214.40/321.12 = 171.20/x
  3. Step 3: Cross multiply
    214.40x = 321.12 × 171.20
  4. Step 4: Simplify right side
    214.40x = 54,975.74
  5. Step 5: Solve for x
    x = 54,975.74/214.40
  6. Step 6: Final answer
    x = 256.42

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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.