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Finding the Fourth Proportional to 118.80, 163.78 and 101.28

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Solution

The fourth proportional to 118.80, 163.78 and 101.28 is: 139.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    118.80 : 163.78 = 101.28 : x
  2. Step 2: Convert to fraction form
    118.80/163.78 = 101.28/x
  3. Step 3: Cross multiply
    118.80x = 163.78 × 101.28
  4. Step 4: Simplify right side
    118.80x = 16,587.64
  5. Step 5: Solve for x
    x = 16,587.64/118.80
  6. Step 6: Final answer
    x = 139.63

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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.