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Finding the Fourth Proportional to 109.65, 151.30 and 68.21

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Solution

The fourth proportional to 109.65, 151.30 and 68.21 is: 94.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    109.65 : 151.30 = 68.21 : x
  2. Step 2: Convert to fraction form
    109.65/151.30 = 68.21/x
  3. Step 3: Cross multiply
    109.65x = 151.30 × 68.21
  4. Step 4: Simplify right side
    109.65x = 10,319.83
  5. Step 5: Solve for x
    x = 10,319.83/109.65
  6. Step 6: Final answer
    x = 94.12

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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.