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Finding the Fourth Proportional to 402.79, 555.72 and 278.47

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Solution

The fourth proportional to 402.79, 555.72 and 278.47 is: 384.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.79 : 555.72 = 278.47 : x
  2. Step 2: Convert to fraction form
    402.79/555.72 = 278.47/x
  3. Step 3: Cross multiply
    402.79x = 555.72 × 278.47
  4. Step 4: Simplify right side
    402.79x = 154,751.35
  5. Step 5: Solve for x
    x = 154,751.35/402.79
  6. Step 6: Final answer
    x = 384.20

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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.