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Finding the Fourth Proportional to 15.83, 21.89 and 13.40

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Solution

The fourth proportional to 15.83, 21.89 and 13.40 is: 18.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.83 : 21.89 = 13.40 : x
  2. Step 2: Convert to fraction form
    15.83/21.89 = 13.40/x
  3. Step 3: Cross multiply
    15.83x = 21.89 × 13.40
  4. Step 4: Simplify right side
    15.83x = 293.33
  5. Step 5: Solve for x
    x = 293.33/15.83
  6. Step 6: Final answer
    x = 18.53

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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.