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Finding the Fourth Proportional to 30.75, 42.45 and 19.25

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Solution

The fourth proportional to 30.75, 42.45 and 19.25 is: 26.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.75 : 42.45 = 19.25 : x
  2. Step 2: Convert to fraction form
    30.75/42.45 = 19.25/x
  3. Step 3: Cross multiply
    30.75x = 42.45 × 19.25
  4. Step 4: Simplify right side
    30.75x = 817.16
  5. Step 5: Solve for x
    x = 817.16/30.75
  6. Step 6: Final answer
    x = 26.57

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Find fourth proportional to 15.38, 21.23 and 9.63
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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.