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Finding the Fourth Proportional to 285.79, 428.69 and 103.19

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Solution

The fourth proportional to 285.79, 428.69 and 103.19 is: 154.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.79 : 428.69 = 103.19 : x
  2. Step 2: Convert to fraction form
    285.79/428.69 = 103.19/x
  3. Step 3: Cross multiply
    285.79x = 428.69 × 103.19
  4. Step 4: Simplify right side
    285.79x = 44,236.52
  5. Step 5: Solve for x
    x = 44,236.52/285.79
  6. Step 6: Final answer
    x = 154.79

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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.