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Finding the Fourth Proportional to 305.10, 420.39 and 291.33

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Solution

The fourth proportional to 305.10, 420.39 and 291.33 is: 401.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.10 : 420.39 = 291.33 : x
  2. Step 2: Convert to fraction form
    305.10/420.39 = 291.33/x
  3. Step 3: Cross multiply
    305.10x = 420.39 × 291.33
  4. Step 4: Simplify right side
    305.10x = 122,472.22
  5. Step 5: Solve for x
    x = 122,472.22/305.10
  6. Step 6: Final answer
    x = 401.42

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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.