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Finding the Third Proportional to 309.19 and 436.78

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Solution

The third proportional to 309.19 and 436.78 is: 617.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.19 : 436.78 = 436.78 : x
  2. Step 2: Convert to fraction form
    309.19/436.78 = 436.78/x
  3. Step 3: Cross multiply
    309.19x = 436.78 × 436.78
  4. Step 4: Simplify right side
    309.19x = 190,777.86
  5. Step 5: Solve for x
    x = 190,777.86/309.19
  6. Step 6: Final answer
    x = 617.03

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Why These Related Problems?

These problems maintain the same ratio (1.41) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.