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Finding the Fourth Proportional to 453.40, 680.10 and 128.77

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Solution

The fourth proportional to 453.40, 680.10 and 128.77 is: 193.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    453.40 : 680.10 = 128.77 : x
  2. Step 2: Convert to fraction form
    453.40/680.10 = 128.77/x
  3. Step 3: Cross multiply
    453.40x = 680.10 × 128.77
  4. Step 4: Simplify right side
    453.40x = 87,572.43
  5. Step 5: Solve for x
    x = 87,572.43/453.40
  6. Step 6: Final answer
    x = 193.15

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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.