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Finding the Fourth Proportional to 428.62, 643.02 and 360.76

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Solution

The fourth proportional to 428.62, 643.02 and 360.76 is: 541.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.62 : 643.02 = 360.76 : x
  2. Step 2: Convert to fraction form
    428.62/643.02 = 360.76/x
  3. Step 3: Cross multiply
    428.62x = 643.02 × 360.76
  4. Step 4: Simplify right side
    428.62x = 231,975.90
  5. Step 5: Solve for x
    x = 231,975.90/428.62
  6. Step 6: Final answer
    x = 541.22

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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.