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Finding the Fourth Proportional to 428.63, 643.85 and 246.38

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Solution

The fourth proportional to 428.63, 643.85 and 246.38 is: 370.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.63 : 643.85 = 246.38 : x
  2. Step 2: Convert to fraction form
    428.63/643.85 = 246.38/x
  3. Step 3: Cross multiply
    428.63x = 643.85 × 246.38
  4. Step 4: Simplify right side
    428.63x = 158,628.24
  5. Step 5: Solve for x
    x = 158,628.24/428.63
  6. Step 6: Final answer
    x = 370.09

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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.