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Finding the Fourth Proportional to 103.88, 143.58 and 79.28

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Solution

The fourth proportional to 103.88, 143.58 and 79.28 is: 109.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.88 : 143.58 = 79.28 : x
  2. Step 2: Convert to fraction form
    103.88/143.58 = 79.28/x
  3. Step 3: Cross multiply
    103.88x = 143.58 × 79.28
  4. Step 4: Simplify right side
    103.88x = 11,383.02
  5. Step 5: Solve for x
    x = 11,383.02/103.88
  6. Step 6: Final answer
    x = 109.58

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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.