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Finding the Fourth Proportional to 123.42, 170.28 and 90.62

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Solution

The fourth proportional to 123.42, 170.28 and 90.62 is: 125.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.42 : 170.28 = 90.62 : x
  2. Step 2: Convert to fraction form
    123.42/170.28 = 90.62/x
  3. Step 3: Cross multiply
    123.42x = 170.28 × 90.62
  4. Step 4: Simplify right side
    123.42x = 15,429.92
  5. Step 5: Solve for x
    x = 15,429.92/123.42
  6. Step 6: Final answer
    x = 125.02

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.