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Finding the Fourth Proportional to 102.90, 154.35 and 89.13

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Solution

The fourth proportional to 102.90, 154.35 and 89.13 is: 133.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.90 : 154.35 = 89.13 : x
  2. Step 2: Convert to fraction form
    102.90/154.35 = 89.13/x
  3. Step 3: Cross multiply
    102.90x = 154.35 × 89.13
  4. Step 4: Simplify right side
    102.90x = 13,757.22
  5. Step 5: Solve for x
    x = 13,757.22/102.90
  6. Step 6: Final answer
    x = 133.70

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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.