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Finding the Fourth Proportional to 438.70, 659.13 and 256.18

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Solution

The fourth proportional to 438.70, 659.13 and 256.18 is: 384.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.70 : 659.13 = 256.18 : x
  2. Step 2: Convert to fraction form
    438.70/659.13 = 256.18/x
  3. Step 3: Cross multiply
    438.70x = 659.13 × 256.18
  4. Step 4: Simplify right side
    438.70x = 168,855.92
  5. Step 5: Solve for x
    x = 168,855.92/438.70
  6. Step 6: Final answer
    x = 384.90

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.