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Finding the Fourth Proportional to 428.67, 645.57 and 375.21

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Solution

The fourth proportional to 428.67, 645.57 and 375.21 is: 565.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.67 : 645.57 = 375.21 : x
  2. Step 2: Convert to fraction form
    428.67/645.57 = 375.21/x
  3. Step 3: Cross multiply
    428.67x = 645.57 × 375.21
  4. Step 4: Simplify right side
    428.67x = 242,224.32
  5. Step 5: Solve for x
    x = 242,224.32/428.67
  6. Step 6: Final answer
    x = 565.06

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.