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Finding the Fourth Proportional to 342.72, 473.10 and 309.90

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Solution

The fourth proportional to 342.72, 473.10 and 309.90 is: 427.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.72 : 473.10 = 309.90 : x
  2. Step 2: Convert to fraction form
    342.72/473.10 = 309.90/x
  3. Step 3: Cross multiply
    342.72x = 473.10 × 309.90
  4. Step 4: Simplify right side
    342.72x = 146,613.69
  5. Step 5: Solve for x
    x = 146,613.69/342.72
  6. Step 6: Final answer
    x = 427.79

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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.