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Finding the Fourth Proportional to 281.40, 421.90 and 171.88

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Solution

The fourth proportional to 281.40, 421.90 and 171.88 is: 257.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.40 : 421.90 = 171.88 : x
  2. Step 2: Convert to fraction form
    281.40/421.90 = 171.88/x
  3. Step 3: Cross multiply
    281.40x = 421.90 × 171.88
  4. Step 4: Simplify right side
    281.40x = 72,516.17
  5. Step 5: Solve for x
    x = 72,516.17/281.40
  6. Step 6: Final answer
    x = 257.70

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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.