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Finding the Fourth Proportional to 309.19, 429.45 and 300.55

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Solution

The fourth proportional to 309.19, 429.45 and 300.55 is: 417.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.19 : 429.45 = 300.55 : x
  2. Step 2: Convert to fraction form
    309.19/429.45 = 300.55/x
  3. Step 3: Cross multiply
    309.19x = 429.45 × 300.55
  4. Step 4: Simplify right side
    309.19x = 129,071.20
  5. Step 5: Solve for x
    x = 129,071.20/309.19
  6. Step 6: Final answer
    x = 417.45

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.