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Finding the Fourth Proportional to 30.69, 42.39 and 25.50

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Solution

The fourth proportional to 30.69, 42.39 and 25.50 is: 35.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.69 : 42.39 = 25.50 : x
  2. Step 2: Convert to fraction form
    30.69/42.39 = 25.50/x
  3. Step 3: Cross multiply
    30.69x = 42.39 × 25.50
  4. Step 4: Simplify right side
    30.69x = 1,080.95
  5. Step 5: Solve for x
    x = 1,080.95/30.69
  6. Step 6: Final answer
    x = 35.22

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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.