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Finding the Fourth Proportional to 101.70, 140.49 and 90.09

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Solution

The fourth proportional to 101.70, 140.49 and 90.09 is: 124.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.70 : 140.49 = 90.09 : x
  2. Step 2: Convert to fraction form
    101.70/140.49 = 90.09/x
  3. Step 3: Cross multiply
    101.70x = 140.49 × 90.09
  4. Step 4: Simplify right side
    101.70x = 12,656.74
  5. Step 5: Solve for x
    x = 12,656.74/101.70
  6. Step 6: Final answer
    x = 124.45

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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.