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Finding the Fourth Proportional to 21.69, 29.96 and 18

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Solution

The fourth proportional to 21.69, 29.96 and 18 is: 24.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.69 : 29.96 = 18 : x
  2. Step 2: Convert to fraction form
    21.69/29.96 = 18/x
  3. Step 3: Cross multiply
    21.69x = 29.96 × 18
  4. Step 4: Simplify right side
    21.69x = 539.28
  5. Step 5: Solve for x
    x = 539.28/21.69
  6. Step 6: Final answer
    x = 24.86

Related Problems

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1.5x scale

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.