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Finding the Fourth Proportional to 387.00, 534.09 and 221.22

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Solution

The fourth proportional to 387.00, 534.09 and 221.22 is: 305.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.00 : 534.09 = 221.22 : x
  2. Step 2: Convert to fraction form
    387.00/534.09 = 221.22/x
  3. Step 3: Cross multiply
    387.00x = 534.09 × 221.22
  4. Step 4: Simplify right side
    387.00x = 118,153.28
  5. Step 5: Solve for x
    x = 118,153.28/387.00
  6. Step 6: Final answer
    x = 305.31

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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.