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Finding the Fourth Proportional to 310.79, 428.66 and 291.89

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Solution

The fourth proportional to 310.79, 428.66 and 291.89 is: 402.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.79 : 428.66 = 291.89 : x
  2. Step 2: Convert to fraction form
    310.79/428.66 = 291.89/x
  3. Step 3: Cross multiply
    310.79x = 428.66 × 291.89
  4. Step 4: Simplify right side
    310.79x = 125,120.11
  5. Step 5: Solve for x
    x = 125,120.11/310.79
  6. Step 6: Final answer
    x = 402.59

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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.