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Finding the Fourth Proportional to 279.40, 385.30 and 220.36

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Solution

The fourth proportional to 279.40, 385.30 and 220.36 is: 303.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.40 : 385.30 = 220.36 : x
  2. Step 2: Convert to fraction form
    279.40/385.30 = 220.36/x
  3. Step 3: Cross multiply
    279.40x = 385.30 × 220.36
  4. Step 4: Simplify right side
    279.40x = 84,904.71
  5. Step 5: Solve for x
    x = 84,904.71/279.40
  6. Step 6: Final answer
    x = 303.88

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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.