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Finding the Fourth Proportional to 257.21, 354.96 and 145.20

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Solution

The fourth proportional to 257.21, 354.96 and 145.20 is: 200.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.21 : 354.96 = 145.20 : x
  2. Step 2: Convert to fraction form
    257.21/354.96 = 145.20/x
  3. Step 3: Cross multiply
    257.21x = 354.96 × 145.20
  4. Step 4: Simplify right side
    257.21x = 51,540.19
  5. Step 5: Solve for x
    x = 51,540.19/257.21
  6. Step 6: Final answer
    x = 200.39

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.