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Finding the Fourth Proportional to 313.32, 428.55 and 308.28

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Solution

The fourth proportional to 313.32, 428.55 and 308.28 is: 421.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    313.32 : 428.55 = 308.28 : x
  2. Step 2: Convert to fraction form
    313.32/428.55 = 308.28/x
  3. Step 3: Cross multiply
    313.32x = 428.55 × 308.28
  4. Step 4: Simplify right side
    313.32x = 132,111.85
  5. Step 5: Solve for x
    x = 132,111.85/313.32
  6. Step 6: Final answer
    x = 421.65

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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.