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Finding the Fourth Proportional to 287.10, 396.50 and 220.95

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Solution

The fourth proportional to 287.10, 396.50 and 220.95 is: 305.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.10 : 396.50 = 220.95 : x
  2. Step 2: Convert to fraction form
    287.10/396.50 = 220.95/x
  3. Step 3: Cross multiply
    287.10x = 396.50 × 220.95
  4. Step 4: Simplify right side
    287.10x = 87,605.57
  5. Step 5: Solve for x
    x = 87,605.57/287.10
  6. Step 6: Final answer
    x = 305.14

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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.