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Finding the Fourth Proportional to 427.47, 639.99 and 393.45

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Solution

The fourth proportional to 427.47, 639.99 and 393.45 is: 589.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.47 : 639.99 = 393.45 : x
  2. Step 2: Convert to fraction form
    427.47/639.99 = 393.45/x
  3. Step 3: Cross multiply
    427.47x = 639.99 × 393.45
  4. Step 4: Simplify right side
    427.47x = 251,804.07
  5. Step 5: Solve for x
    x = 251,804.07/427.47
  6. Step 6: Final answer
    x = 589.06

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.