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Finding the Fourth Proportional to 30.69, 42.21 and 29.43

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Solution

The fourth proportional to 30.69, 42.21 and 29.43 is: 40.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.69 : 42.21 = 29.43 : x
  2. Step 2: Convert to fraction form
    30.69/42.21 = 29.43/x
  3. Step 3: Cross multiply
    30.69x = 42.21 × 29.43
  4. Step 4: Simplify right side
    30.69x = 1,242.24
  5. Step 5: Solve for x
    x = 1,242.24/30.69
  6. Step 6: Final answer
    x = 40.48

Related Problems

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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.