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Finding the Fourth Proportional to 428.80, 642.96 and 377.56

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Solution

The fourth proportional to 428.80, 642.96 and 377.56 is: 566.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.80 : 642.96 = 377.56 : x
  2. Step 2: Convert to fraction form
    428.80/642.96 = 377.56/x
  3. Step 3: Cross multiply
    428.80x = 642.96 × 377.56
  4. Step 4: Simplify right side
    428.80x = 242,755.98
  5. Step 5: Solve for x
    x = 242,755.98/428.80
  6. Step 6: Final answer
    x = 566.13

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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.