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Finding the Fourth Proportional to 90.62, 125.05 and 51.28

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Solution

The fourth proportional to 90.62, 125.05 and 51.28 is: 70.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.62 : 125.05 = 51.28 : x
  2. Step 2: Convert to fraction form
    90.62/125.05 = 51.28/x
  3. Step 3: Cross multiply
    90.62x = 125.05 × 51.28
  4. Step 4: Simplify right side
    90.62x = 6,412.56
  5. Step 5: Solve for x
    x = 6,412.56/90.62
  6. Step 6: Final answer
    x = 70.76

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.