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Finding the Fourth Proportional to 388.30, 581.10 and 272.20

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Solution

The fourth proportional to 388.30, 581.10 and 272.20 is: 407.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.30 : 581.10 = 272.20 : x
  2. Step 2: Convert to fraction form
    388.30/581.10 = 272.20/x
  3. Step 3: Cross multiply
    388.30x = 581.10 × 272.20
  4. Step 4: Simplify right side
    388.30x = 158,175.42
  5. Step 5: Solve for x
    x = 158,175.42/388.30
  6. Step 6: Final answer
    x = 407.35

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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.