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Finding the Fourth Proportional to 386.96, 579.72 and 278.48

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Solution

The fourth proportional to 386.96, 579.72 and 278.48 is: 417.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.96 : 579.72 = 278.48 : x
  2. Step 2: Convert to fraction form
    386.96/579.72 = 278.48/x
  3. Step 3: Cross multiply
    386.96x = 579.72 × 278.48
  4. Step 4: Simplify right side
    386.96x = 161,440.43
  5. Step 5: Solve for x
    x = 161,440.43/386.96
  6. Step 6: Final answer
    x = 417.20

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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.