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Finding the Fourth Proportional to 388.90, 536.67 and 218.55

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Solution

The fourth proportional to 388.90, 536.67 and 218.55 is: 301.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.90 : 536.67 = 218.55 : x
  2. Step 2: Convert to fraction form
    388.90/536.67 = 218.55/x
  3. Step 3: Cross multiply
    388.90x = 536.67 × 218.55
  4. Step 4: Simplify right side
    388.90x = 117,289.23
  5. Step 5: Solve for x
    x = 117,289.23/388.90
  6. Step 6: Final answer
    x = 301.59

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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.