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Finding the Fourth Proportional to 27.68, 38.08 and 21.20

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Solution

The fourth proportional to 27.68, 38.08 and 21.20 is: 29.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    27.68 : 38.08 = 21.20 : x
  2. Step 2: Convert to fraction form
    27.68/38.08 = 21.20/x
  3. Step 3: Cross multiply
    27.68x = 38.08 × 21.20
  4. Step 4: Simplify right side
    27.68x = 807.30
  5. Step 5: Solve for x
    x = 807.30/27.68
  6. Step 6: Final answer
    x = 29.17

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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.