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Finding the Fourth Proportional to 427.53, 643.61 and 389.26

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Solution

The fourth proportional to 427.53, 643.61 and 389.26 is: 585.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.53 : 643.61 = 389.26 : x
  2. Step 2: Convert to fraction form
    427.53/643.61 = 389.26/x
  3. Step 3: Cross multiply
    427.53x = 643.61 × 389.26
  4. Step 4: Simplify right side
    427.53x = 250,528.14
  5. Step 5: Solve for x
    x = 250,528.14/427.53
  6. Step 6: Final answer
    x = 585.99

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.