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Finding the Fourth Proportional to 103.42, 142.78 and 80.06

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Solution

The fourth proportional to 103.42, 142.78 and 80.06 is: 110.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.42 : 142.78 = 80.06 : x
  2. Step 2: Convert to fraction form
    103.42/142.78 = 80.06/x
  3. Step 3: Cross multiply
    103.42x = 142.78 × 80.06
  4. Step 4: Simplify right side
    103.42x = 11,430.97
  5. Step 5: Solve for x
    x = 11,430.97/103.42
  6. Step 6: Final answer
    x = 110.53

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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.