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Finding the Fourth Proportional to 389.07, 536.36 and 330.21

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Solution

The fourth proportional to 389.07, 536.36 and 330.21 is: 455.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.07 : 536.36 = 330.21 : x
  2. Step 2: Convert to fraction form
    389.07/536.36 = 330.21/x
  3. Step 3: Cross multiply
    389.07x = 536.36 × 330.21
  4. Step 4: Simplify right side
    389.07x = 177,109.78
  5. Step 5: Solve for x
    x = 177,109.78/389.07
  6. Step 6: Final answer
    x = 455.21

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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.