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Finding the Fourth Proportional to 27.69, 38.19 and 21.55

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Solution

The fourth proportional to 27.69, 38.19 and 21.55 is: 29.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    27.69 : 38.19 = 21.55 : x
  2. Step 2: Convert to fraction form
    27.69/38.19 = 21.55/x
  3. Step 3: Cross multiply
    27.69x = 38.19 × 21.55
  4. Step 4: Simplify right side
    27.69x = 822.99
  5. Step 5: Solve for x
    x = 822.99/27.69
  6. Step 6: Final answer
    x = 29.72

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1.5x scale

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.