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Finding the Fourth Proportional to 386.09, 579.20 and 256.35

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Solution

The fourth proportional to 386.09, 579.20 and 256.35 is: 384.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.09 : 579.20 = 256.35 : x
  2. Step 2: Convert to fraction form
    386.09/579.20 = 256.35/x
  3. Step 3: Cross multiply
    386.09x = 579.20 × 256.35
  4. Step 4: Simplify right side
    386.09x = 148,477.92
  5. Step 5: Solve for x
    x = 148,477.92/386.09
  6. Step 6: Final answer
    x = 384.57

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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.