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Finding the Fourth Proportional to 89.30, 134.08 and 72.42

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Solution

The fourth proportional to 89.30, 134.08 and 72.42 is: 108.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    89.30 : 134.08 = 72.42 : x
  2. Step 2: Convert to fraction form
    89.30/134.08 = 72.42/x
  3. Step 3: Cross multiply
    89.30x = 134.08 × 72.42
  4. Step 4: Simplify right side
    89.30x = 9,710.07
  5. Step 5: Solve for x
    x = 9,710.07/89.30
  6. Step 6: Final answer
    x = 108.74

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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.