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Finding the Fourth Proportional to 90.10, 124.23 and 66.79

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Solution

The fourth proportional to 90.10, 124.23 and 66.79 is: 92.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.10 : 124.23 = 66.79 : x
  2. Step 2: Convert to fraction form
    90.10/124.23 = 66.79/x
  3. Step 3: Cross multiply
    90.10x = 124.23 × 66.79
  4. Step 4: Simplify right side
    90.10x = 8,297.32
  5. Step 5: Solve for x
    x = 8,297.32/90.10
  6. Step 6: Final answer
    x = 92.09

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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.