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Finding the Fourth Proportional to 312.40, 428.41 and 296.60

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Solution

The fourth proportional to 312.40, 428.41 and 296.60 is: 406.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.40 : 428.41 = 296.60 : x
  2. Step 2: Convert to fraction form
    312.40/428.41 = 296.60/x
  3. Step 3: Cross multiply
    312.40x = 428.41 × 296.60
  4. Step 4: Simplify right side
    312.40x = 127,066.74
  5. Step 5: Solve for x
    x = 127,066.74/312.40
  6. Step 6: Final answer
    x = 406.75

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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.