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Finding the Fourth Proportional to 219.28, 328.95 and 80.50

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Solution

The fourth proportional to 219.28, 328.95 and 80.50 is: 120.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.28 : 328.95 = 80.50 : x
  2. Step 2: Convert to fraction form
    219.28/328.95 = 80.50/x
  3. Step 3: Cross multiply
    219.28x = 328.95 × 80.50
  4. Step 4: Simplify right side
    219.28x = 26,478.43
  5. Step 5: Solve for x
    x = 26,478.43/219.28
  6. Step 6: Final answer
    x = 120.75

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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.