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Finding the Fourth Proportional to 428.57, 642.60 and 377.31

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Solution

The fourth proportional to 428.57, 642.60 and 377.31 is: 565.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.57 : 642.60 = 377.31 : x
  2. Step 2: Convert to fraction form
    428.57/642.60 = 377.31/x
  3. Step 3: Cross multiply
    428.57x = 642.60 × 377.31
  4. Step 4: Simplify right side
    428.57x = 242,459.41
  5. Step 5: Solve for x
    x = 242,459.41/428.57
  6. Step 6: Final answer
    x = 565.75

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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.