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Finding the Fourth Proportional to 381.51, 572.40 and 219.15

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Solution

The fourth proportional to 381.51, 572.40 and 219.15 is: 328.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.51 : 572.40 = 219.15 : x
  2. Step 2: Convert to fraction form
    381.51/572.40 = 219.15/x
  3. Step 3: Cross multiply
    381.51x = 572.40 × 219.15
  4. Step 4: Simplify right side
    381.51x = 125,441.46
  5. Step 5: Solve for x
    x = 125,441.46/381.51
  6. Step 6: Final answer
    x = 328.80

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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.