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Finding the Fourth Proportional to 171.20, 256.84 and 90.08

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Solution

The fourth proportional to 171.20, 256.84 and 90.08 is: 135.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.20 : 256.84 = 90.08 : x
  2. Step 2: Convert to fraction form
    171.20/256.84 = 90.08/x
  3. Step 3: Cross multiply
    171.20x = 256.84 × 90.08
  4. Step 4: Simplify right side
    171.20x = 23,136.15
  5. Step 5: Solve for x
    x = 23,136.15/171.20
  6. Step 6: Final answer
    x = 135.14

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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.