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Finding the Fourth Proportional to 428.48, 642.94 and 306.58

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Solution

The fourth proportional to 428.48, 642.94 and 306.58 is: 460.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.48 : 642.94 = 306.58 : x
  2. Step 2: Convert to fraction form
    428.48/642.94 = 306.58/x
  3. Step 3: Cross multiply
    428.48x = 642.94 × 306.58
  4. Step 4: Simplify right side
    428.48x = 197,112.55
  5. Step 5: Solve for x
    x = 197,112.55/428.48
  6. Step 6: Final answer
    x = 460.03

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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.