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Finding the Fourth Proportional to 25.50, 35.19 and 15.80

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Solution

The fourth proportional to 25.50, 35.19 and 15.80 is: 21.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.50 : 35.19 = 15.80 : x
  2. Step 2: Convert to fraction form
    25.50/35.19 = 15.80/x
  3. Step 3: Cross multiply
    25.50x = 35.19 × 15.80
  4. Step 4: Simplify right side
    25.50x = 556.09
  5. Step 5: Solve for x
    x = 556.09/25.50
  6. Step 6: Final answer
    x = 21.81

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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.