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Finding the Fourth Proportional to 402.50, 555.72 and 304.78

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Solution

The fourth proportional to 402.50, 555.72 and 304.78 is: 420.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    402.50 : 555.72 = 304.78 : x
  2. Step 2: Convert to fraction form
    402.50/555.72 = 304.78/x
  3. Step 3: Cross multiply
    402.50x = 555.72 × 304.78
  4. Step 4: Simplify right side
    402.50x = 169,372.34
  5. Step 5: Solve for x
    x = 169,372.34/402.50
  6. Step 6: Final answer
    x = 420.80

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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.