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Finding the Fourth Proportional to 27.99, 38.58 and 19.80

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Solution

The fourth proportional to 27.99, 38.58 and 19.80 is: 27.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    27.99 : 38.58 = 19.80 : x
  2. Step 2: Convert to fraction form
    27.99/38.58 = 19.80/x
  3. Step 3: Cross multiply
    27.99x = 38.58 × 19.80
  4. Step 4: Simplify right side
    27.99x = 763.88
  5. Step 5: Solve for x
    x = 763.88/27.99
  6. Step 6: Final answer
    x = 27.29

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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.