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Finding the Fourth Proportional to 386.89, 533.88 and 221.07

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Solution

The fourth proportional to 386.89, 533.88 and 221.07 is: 305.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.89 : 533.88 = 221.07 : x
  2. Step 2: Convert to fraction form
    386.89/533.88 = 221.07/x
  3. Step 3: Cross multiply
    386.89x = 533.88 × 221.07
  4. Step 4: Simplify right side
    386.89x = 118,023.75
  5. Step 5: Solve for x
    x = 118,023.75/386.89
  6. Step 6: Final answer
    x = 305.06

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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.