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Finding the Fourth Proportional to 90.15, 134.63 and 72.06

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Solution

The fourth proportional to 90.15, 134.63 and 72.06 is: 107.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    90.15 : 134.63 = 72.06 : x
  2. Step 2: Convert to fraction form
    90.15/134.63 = 72.06/x
  3. Step 3: Cross multiply
    90.15x = 134.63 × 72.06
  4. Step 4: Simplify right side
    90.15x = 9,701.44
  5. Step 5: Solve for x
    x = 9,701.44/90.15
  6. Step 6: Final answer
    x = 107.61

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.