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Finding the Fourth Proportional to 103.88, 142.58 and 100.28

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Solution

The fourth proportional to 103.88, 142.58 and 100.28 is: 137.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.88 : 142.58 = 100.28 : x
  2. Step 2: Convert to fraction form
    103.88/142.58 = 100.28/x
  3. Step 3: Cross multiply
    103.88x = 142.58 × 100.28
  4. Step 4: Simplify right side
    103.88x = 14,297.92
  5. Step 5: Solve for x
    x = 14,297.92/103.88
  6. Step 6: Final answer
    x = 137.64

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.