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Finding the Fourth Proportional to 389.22, 536.39 and 278.50

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Solution

The fourth proportional to 389.22, 536.39 and 278.50 is: 383.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.22 : 536.39 = 278.50 : x
  2. Step 2: Convert to fraction form
    389.22/536.39 = 278.50/x
  3. Step 3: Cross multiply
    389.22x = 536.39 × 278.50
  4. Step 4: Simplify right side
    389.22x = 149,384.56
  5. Step 5: Solve for x
    x = 149,384.56/389.22
  6. Step 6: Final answer
    x = 383.80

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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.