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Finding the Fourth Proportional to 128.49, 191.49 and 128.29

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Solution

The fourth proportional to 128.49, 191.49 and 128.29 is: 191.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.49 : 191.49 = 128.29 : x
  2. Step 2: Convert to fraction form
    128.49/191.49 = 128.29/x
  3. Step 3: Cross multiply
    128.49x = 191.49 × 128.29
  4. Step 4: Simplify right side
    128.49x = 24,565.29
  5. Step 5: Solve for x
    x = 24,565.29/128.49
  6. Step 6: Final answer
    x = 191.19

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.