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Finding the Fourth Proportional to 313.07, 428.20 and 308.03

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Solution

The fourth proportional to 313.07, 428.20 and 308.03 is: 421.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    313.07 : 428.20 = 308.03 : x
  2. Step 2: Convert to fraction form
    313.07/428.20 = 308.03/x
  3. Step 3: Cross multiply
    313.07x = 428.20 × 308.03
  4. Step 4: Simplify right side
    313.07x = 131,899.22
  5. Step 5: Solve for x
    x = 131,899.22/313.07
  6. Step 6: Final answer
    x = 421.31

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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.