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Finding the Fourth Proportional to 90.15, 135.42 and 55.98

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Solution

The fourth proportional to 90.15, 135.42 and 55.98 is: 84.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.15 : 135.42 = 55.98 : x
  2. Step 2: Convert to fraction form
    90.15/135.42 = 55.98/x
  3. Step 3: Cross multiply
    90.15x = 135.42 × 55.98
  4. Step 4: Simplify right side
    90.15x = 7,580.81
  5. Step 5: Solve for x
    x = 7,580.81/90.15
  6. Step 6: Final answer
    x = 84.09

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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.