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Finding the Fourth Proportional to 285.70, 428.40 and 123.19

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Solution

The fourth proportional to 285.70, 428.40 and 123.19 is: 184.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.70 : 428.40 = 123.19 : x
  2. Step 2: Convert to fraction form
    285.70/428.40 = 123.19/x
  3. Step 3: Cross multiply
    285.70x = 428.40 × 123.19
  4. Step 4: Simplify right side
    285.70x = 52,774.60
  5. Step 5: Solve for x
    x = 52,774.60/285.70
  6. Step 6: Final answer
    x = 184.72

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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.