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Finding the Fourth Proportional to 219.29, 328.82 and 128.00

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Solution

The fourth proportional to 219.29, 328.82 and 128.00 is: 191.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.29 : 328.82 = 128.00 : x
  2. Step 2: Convert to fraction form
    219.29/328.82 = 128.00/x
  3. Step 3: Cross multiply
    219.29x = 328.82 × 128.00
  4. Step 4: Simplify right side
    219.29x = 42,086.68
  5. Step 5: Solve for x
    x = 42,086.68/219.29
  6. Step 6: Final answer
    x = 191.93

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.