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Finding the Fourth Proportional to 285.38, 428.31 and 228.74

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Solution

The fourth proportional to 285.38, 428.31 and 228.74 is: 343.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.38 : 428.31 = 228.74 : x
  2. Step 2: Convert to fraction form
    285.38/428.31 = 228.74/x
  3. Step 3: Cross multiply
    285.38x = 428.31 × 228.74
  4. Step 4: Simplify right side
    285.38x = 97,971.63
  5. Step 5: Solve for x
    x = 97,971.63/285.38
  6. Step 6: Final answer
    x = 343.30

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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.