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Finding the Fourth Proportional to 388.21, 535.74 and 213.55

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Solution

The fourth proportional to 388.21, 535.74 and 213.55 is: 294.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.21 : 535.74 = 213.55 : x
  2. Step 2: Convert to fraction form
    388.21/535.74 = 213.55/x
  3. Step 3: Cross multiply
    388.21x = 535.74 × 213.55
  4. Step 4: Simplify right side
    388.21x = 114,407.28
  5. Step 5: Solve for x
    x = 114,407.28/388.21
  6. Step 6: Final answer
    x = 294.70

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.