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Finding the Fourth Proportional to 287.55, 397.01 and 221.05

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Solution

The fourth proportional to 287.55, 397.01 and 221.05 is: 305.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.55 : 397.01 = 221.05 : x
  2. Step 2: Convert to fraction form
    287.55/397.01 = 221.05/x
  3. Step 3: Cross multiply
    287.55x = 397.01 × 221.05
  4. Step 4: Simplify right side
    287.55x = 87,757.63
  5. Step 5: Solve for x
    x = 87,757.63/287.55
  6. Step 6: Final answer
    x = 305.19

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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.