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Finding the Fourth Proportional to 388.62, 536.46 and 305.55

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Solution

The fourth proportional to 388.62, 536.46 and 305.55 is: 421.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.62 : 536.46 = 305.55 : x
  2. Step 2: Convert to fraction form
    388.62/536.46 = 305.55/x
  3. Step 3: Cross multiply
    388.62x = 536.46 × 305.55
  4. Step 4: Simplify right side
    388.62x = 163,915.35
  5. Step 5: Solve for x
    x = 163,915.35/388.62
  6. Step 6: Final answer
    x = 421.79

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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.