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Finding the Fourth Proportional to 306.60, 428.70 and 306.60

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Solution

The fourth proportional to 306.60, 428.70 and 306.60 is: 428.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.60 : 428.70 = 306.60 : x
  2. Step 2: Convert to fraction form
    306.60/428.70 = 306.60/x
  3. Step 3: Cross multiply
    306.60x = 428.70 × 306.60
  4. Step 4: Simplify right side
    306.60x = 131,439.42
  5. Step 5: Solve for x
    x = 131,439.42/306.60
  6. Step 6: Final answer
    x = 428.70

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.