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Finding the Fourth Proportional to 310.42, 428.25 and 199.81

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Solution

The fourth proportional to 310.42, 428.25 and 199.81 is: 275.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.42 : 428.25 = 199.81 : x
  2. Step 2: Convert to fraction form
    310.42/428.25 = 199.81/x
  3. Step 3: Cross multiply
    310.42x = 428.25 × 199.81
  4. Step 4: Simplify right side
    310.42x = 85,568.63
  5. Step 5: Solve for x
    x = 85,568.63/310.42
  6. Step 6: Final answer
    x = 275.65

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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.