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Finding the Fourth Proportional to 312.56, 428.56 and 306.08

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Solution

The fourth proportional to 312.56, 428.56 and 306.08 is: 419.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.56 : 428.56 = 306.08 : x
  2. Step 2: Convert to fraction form
    312.56/428.56 = 306.08/x
  3. Step 3: Cross multiply
    312.56x = 428.56 × 306.08
  4. Step 4: Simplify right side
    312.56x = 131,173.64
  5. Step 5: Solve for x
    x = 131,173.64/312.56
  6. Step 6: Final answer
    x = 419.68

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.