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Finding the Fourth Proportional to 28.55, 42.67 and 21.71

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Solution

The fourth proportional to 28.55, 42.67 and 21.71 is: 32.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.55 : 42.67 = 21.71 : x
  2. Step 2: Convert to fraction form
    28.55/42.67 = 21.71/x
  3. Step 3: Cross multiply
    28.55x = 42.67 × 21.71
  4. Step 4: Simplify right side
    28.55x = 926.37
  5. Step 5: Solve for x
    x = 926.37/28.55
  6. Step 6: Final answer
    x = 32.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.