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Finding the Fourth Proportional to 15.43, 21.31 and 13.00

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Solution

The fourth proportional to 15.43, 21.31 and 13.00 is: 17.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    15.43 : 21.31 = 13.00 : x
  2. Step 2: Convert to fraction form
    15.43/21.31 = 13.00/x
  3. Step 3: Cross multiply
    15.43x = 21.31 × 13.00
  4. Step 4: Simplify right side
    15.43x = 276.94
  5. Step 5: Solve for x
    x = 276.94/15.43
  6. Step 6: Final answer
    x = 17.95

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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.