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Finding the Fourth Proportional to 285.90, 428.58 and 231.90

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Solution

The fourth proportional to 285.90, 428.58 and 231.90 is: 347.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.90 : 428.58 = 231.90 : x
  2. Step 2: Convert to fraction form
    285.90/428.58 = 231.90/x
  3. Step 3: Cross multiply
    285.90x = 428.58 × 231.90
  4. Step 4: Simplify right side
    285.90x = 99,387.70
  5. Step 5: Solve for x
    x = 99,387.70/285.90
  6. Step 6: Final answer
    x = 347.63

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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.