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Finding the Fourth Proportional to 15.08, 20.80 and 11.45

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Solution

The fourth proportional to 15.08, 20.80 and 11.45 is: 15.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.08 : 20.80 = 11.45 : x
  2. Step 2: Convert to fraction form
    15.08/20.80 = 11.45/x
  3. Step 3: Cross multiply
    15.08x = 20.80 × 11.45
  4. Step 4: Simplify right side
    15.08x = 238.23
  5. Step 5: Solve for x
    x = 238.23/15.08
  6. Step 6: Final answer
    x = 15.80

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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.