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Finding the Fourth Proportional to 219.30, 328.80 and 103.80

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Solution

The fourth proportional to 219.30, 328.80 and 103.80 is: 155.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.30 : 328.80 = 103.80 : x
  2. Step 2: Convert to fraction form
    219.30/328.80 = 103.80/x
  3. Step 3: Cross multiply
    219.30x = 328.80 × 103.80
  4. Step 4: Simplify right side
    219.30x = 34,129.44
  5. Step 5: Solve for x
    x = 34,129.44/219.30
  6. Step 6: Final answer
    x = 155.63

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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.