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Finding the Fourth Proportional to 42.28, 58.30 and 30.76

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Solution

The fourth proportional to 42.28, 58.30 and 30.76 is: 42.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.28 : 58.30 = 30.76 : x
  2. Step 2: Convert to fraction form
    42.28/58.30 = 30.76/x
  3. Step 3: Cross multiply
    42.28x = 58.30 × 30.76
  4. Step 4: Simplify right side
    42.28x = 1,793.31
  5. Step 5: Solve for x
    x = 1,793.31/42.28
  6. Step 6: Final answer
    x = 42.42

Related Problems

Find fourth proportional to 21.14, 29.15 and 15.38
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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.