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Finding the Fourth Proportional to 388.42, 535.91 and 305.44

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Solution

The fourth proportional to 388.42, 535.91 and 305.44 is: 421.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.42 : 535.91 = 305.44 : x
  2. Step 2: Convert to fraction form
    388.42/535.91 = 305.44/x
  3. Step 3: Cross multiply
    388.42x = 535.91 × 305.44
  4. Step 4: Simplify right side
    388.42x = 163,685.48
  5. Step 5: Solve for x
    x = 163,685.48/388.42
  6. Step 6: Final answer
    x = 421.42

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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.