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Finding the Fourth Proportional to 386.91, 534.67 and 321.30

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Solution

The fourth proportional to 386.91, 534.67 and 321.30 is: 444.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.91 : 534.67 = 321.30 : x
  2. Step 2: Convert to fraction form
    386.91/534.67 = 321.30/x
  3. Step 3: Cross multiply
    386.91x = 534.67 × 321.30
  4. Step 4: Simplify right side
    386.91x = 171,788.67
  5. Step 5: Solve for x
    x = 171,788.67/386.91
  6. Step 6: Final answer
    x = 444.00

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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.