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Finding the Fourth Proportional to 90.23, 135.05 and 54.05

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Solution

The fourth proportional to 90.23, 135.05 and 54.05 is: 80.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.23 : 135.05 = 54.05 : x
  2. Step 2: Convert to fraction form
    90.23/135.05 = 54.05/x
  3. Step 3: Cross multiply
    90.23x = 135.05 × 54.05
  4. Step 4: Simplify right side
    90.23x = 7,298.51
  5. Step 5: Solve for x
    x = 7,298.51/90.23
  6. Step 6: Final answer
    x = 80.89

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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.