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Finding the Fourth Proportional to 385.20, 577.28 and 220.40

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Solution

The fourth proportional to 385.20, 577.28 and 220.40 is: 330.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.20 : 577.28 = 220.40 : x
  2. Step 2: Convert to fraction form
    385.20/577.28 = 220.40/x
  3. Step 3: Cross multiply
    385.20x = 577.28 × 220.40
  4. Step 4: Simplify right side
    385.20x = 127,232.51
  5. Step 5: Solve for x
    x = 127,232.51/385.20
  6. Step 6: Final answer
    x = 330.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.