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Finding the Fourth Proportional to 389.07, 536.47 and 318.90

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Solution

The fourth proportional to 389.07, 536.47 and 318.90 is: 439.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.07 : 536.47 = 318.90 : x
  2. Step 2: Convert to fraction form
    389.07/536.47 = 318.90/x
  3. Step 3: Cross multiply
    389.07x = 536.47 × 318.90
  4. Step 4: Simplify right side
    389.07x = 171,083.29
  5. Step 5: Solve for x
    x = 171,083.29/389.07
  6. Step 6: Final answer
    x = 439.72

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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.