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Finding the Fourth Proportional to 389.78, 536.31 and 302.30

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Solution

The fourth proportional to 389.78, 536.31 and 302.30 is: 415.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.78 : 536.31 = 302.30 : x
  2. Step 2: Convert to fraction form
    389.78/536.31 = 302.30/x
  3. Step 3: Cross multiply
    389.78x = 536.31 × 302.30
  4. Step 4: Simplify right side
    389.78x = 162,123.83
  5. Step 5: Solve for x
    x = 162,123.83/389.78
  6. Step 6: Final answer
    x = 415.94

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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.