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Finding the Fourth Proportional to 103.07, 141.78 and 90.56

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Solution

The fourth proportional to 103.07, 141.78 and 90.56 is: 124.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.07 : 141.78 = 90.56 : x
  2. Step 2: Convert to fraction form
    103.07/141.78 = 90.56/x
  3. Step 3: Cross multiply
    103.07x = 141.78 × 90.56
  4. Step 4: Simplify right side
    103.07x = 12,839.60
  5. Step 5: Solve for x
    x = 12,839.60/103.07
  6. Step 6: Final answer
    x = 124.57

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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.