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Finding the Fourth Proportional to 102.21, 152.57 and 90.20

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Solution

The fourth proportional to 102.21, 152.57 and 90.20 is: 134.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.21 : 152.57 = 90.20 : x
  2. Step 2: Convert to fraction form
    102.21/152.57 = 90.20/x
  3. Step 3: Cross multiply
    102.21x = 152.57 × 90.20
  4. Step 4: Simplify right side
    102.21x = 13,760.60
  5. Step 5: Solve for x
    x = 13,760.60/102.21
  6. Step 6: Final answer
    x = 134.63

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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.