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Finding the Fourth Proportional to 90.20, 134.96 and 51.70

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Solution

The fourth proportional to 90.20, 134.96 and 51.70 is: 77.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.20 : 134.96 = 51.70 : x
  2. Step 2: Convert to fraction form
    90.20/134.96 = 51.70/x
  3. Step 3: Cross multiply
    90.20x = 134.96 × 51.70
  4. Step 4: Simplify right side
    90.20x = 6,977.64
  5. Step 5: Solve for x
    x = 6,977.64/90.20
  6. Step 6: Final answer
    x = 77.36

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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.