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Finding the Fourth Proportional to 25.59, 35.31 and 21.20

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Solution

The fourth proportional to 25.59, 35.31 and 21.20 is: 29.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    25.59 : 35.31 = 21.20 : x
  2. Step 2: Convert to fraction form
    25.59/35.31 = 21.20/x
  3. Step 3: Cross multiply
    25.59x = 35.31 × 21.20
  4. Step 4: Simplify right side
    25.59x = 748.40
  5. Step 5: Solve for x
    x = 748.40/25.59
  6. Step 6: Final answer
    x = 29.25

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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.