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Finding the Fourth Proportional to 453.30, 679.97 and 128.70

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Solution

The fourth proportional to 453.30, 679.97 and 128.70 is: 193.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    453.30 : 679.97 = 128.70 : x
  2. Step 2: Convert to fraction form
    453.30/679.97 = 128.70/x
  3. Step 3: Cross multiply
    453.30x = 679.97 × 128.70
  4. Step 4: Simplify right side
    453.30x = 87,512.14
  5. Step 5: Solve for x
    x = 87,512.14/453.30
  6. Step 6: Final answer
    x = 193.06

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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.