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Finding the Fourth Proportional to 305.98, 423.24 and 256.78

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Solution

The fourth proportional to 305.98, 423.24 and 256.78 is: 355.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.98 : 423.24 = 256.78 : x
  2. Step 2: Convert to fraction form
    305.98/423.24 = 256.78/x
  3. Step 3: Cross multiply
    305.98x = 423.24 × 256.78
  4. Step 4: Simplify right side
    305.98x = 108,679.57
  5. Step 5: Solve for x
    x = 108,679.57/305.98
  6. Step 6: Final answer
    x = 355.19

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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.