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Finding the Fourth Proportional to 312.49, 428.56 and 296.70

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Solution

The fourth proportional to 312.49, 428.56 and 296.70 is: 406.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.49 : 428.56 = 296.70 : x
  2. Step 2: Convert to fraction form
    312.49/428.56 = 296.70/x
  3. Step 3: Cross multiply
    312.49x = 428.56 × 296.70
  4. Step 4: Simplify right side
    312.49x = 127,151.40
  5. Step 5: Solve for x
    x = 127,151.40/312.49
  6. Step 6: Final answer
    x = 406.90

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.