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Finding the Fourth Proportional to 101.40, 139.79 and 64.54

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Solution

The fourth proportional to 101.40, 139.79 and 64.54 is: 88.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.40 : 139.79 = 64.54 : x
  2. Step 2: Convert to fraction form
    101.40/139.79 = 64.54/x
  3. Step 3: Cross multiply
    101.40x = 139.79 × 64.54
  4. Step 4: Simplify right side
    101.40x = 9,022.05
  5. Step 5: Solve for x
    x = 9,022.05/101.40
  6. Step 6: Final answer
    x = 88.97

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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.