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Finding the Fourth Proportional to 310.40, 428.22 and 205.60

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Solution

The fourth proportional to 310.40, 428.22 and 205.60 is: 283.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.40 : 428.22 = 205.60 : x
  2. Step 2: Convert to fraction form
    310.40/428.22 = 205.60/x
  3. Step 3: Cross multiply
    310.40x = 428.22 × 205.60
  4. Step 4: Simplify right side
    310.40x = 88,042.03
  5. Step 5: Solve for x
    x = 88,042.03/310.40
  6. Step 6: Final answer
    x = 283.64

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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.