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Finding the Fourth Proportional to 388.59, 536.20 and 213.90

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Solution

The fourth proportional to 388.59, 536.20 and 213.90 is: 295.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.59 : 536.20 = 213.90 : x
  2. Step 2: Convert to fraction form
    388.59/536.20 = 213.90/x
  3. Step 3: Cross multiply
    388.59x = 536.20 × 213.90
  4. Step 4: Simplify right side
    388.59x = 114,693.18
  5. Step 5: Solve for x
    x = 114,693.18/388.59
  6. Step 6: Final answer
    x = 295.15

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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.