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Finding the Fourth Proportional to 298.31, 411.80 and 256.70

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Solution

The fourth proportional to 298.31, 411.80 and 256.70 is: 354.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    298.31 : 411.80 = 256.70 : x
  2. Step 2: Convert to fraction form
    298.31/411.80 = 256.70/x
  3. Step 3: Cross multiply
    298.31x = 411.80 × 256.70
  4. Step 4: Simplify right side
    298.31x = 105,708.81
  5. Step 5: Solve for x
    x = 105,708.81/298.31
  6. Step 6: Final answer
    x = 354.36

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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.