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Finding the Fourth Proportional to 311.58, 430.29 and 256.50

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Solution

The fourth proportional to 311.58, 430.29 and 256.50 is: 354.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.58 : 430.29 = 256.50 : x
  2. Step 2: Convert to fraction form
    311.58/430.29 = 256.50/x
  3. Step 3: Cross multiply
    311.58x = 430.29 × 256.50
  4. Step 4: Simplify right side
    311.58x = 110,369.39
  5. Step 5: Solve for x
    x = 110,369.39/311.58
  6. Step 6: Final answer
    x = 354.22

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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.