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Finding the Fourth Proportional to 38.66, 53.38 and 30.88

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Solution

The fourth proportional to 38.66, 53.38 and 30.88 is: 42.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.66 : 53.38 = 30.88 : x
  2. Step 2: Convert to fraction form
    38.66/53.38 = 30.88/x
  3. Step 3: Cross multiply
    38.66x = 53.38 × 30.88
  4. Step 4: Simplify right side
    38.66x = 1,648.37
  5. Step 5: Solve for x
    x = 1,648.37/38.66
  6. Step 6: Final answer
    x = 42.64

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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.