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Finding the Fourth Proportional to 310.50, 428.28 and 199.80

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Solution

The fourth proportional to 310.50, 428.28 and 199.80 is: 275.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.50 : 428.28 = 199.80 : x
  2. Step 2: Convert to fraction form
    310.50/428.28 = 199.80/x
  3. Step 3: Cross multiply
    310.50x = 428.28 × 199.80
  4. Step 4: Simplify right side
    310.50x = 85,570.34
  5. Step 5: Solve for x
    x = 85,570.34/310.50
  6. Step 6: Final answer
    x = 275.59

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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.