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Finding the Fourth Proportional to 309.18, 426.49 and 256.98

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Solution

The fourth proportional to 309.18, 426.49 and 256.98 is: 354.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.18 : 426.49 = 256.98 : x
  2. Step 2: Convert to fraction form
    309.18/426.49 = 256.98/x
  3. Step 3: Cross multiply
    309.18x = 426.49 × 256.98
  4. Step 4: Simplify right side
    309.18x = 109,599.40
  5. Step 5: Solve for x
    x = 109,599.40/309.18
  6. Step 6: Final answer
    x = 354.48

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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.