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Finding the Fourth Proportional to 688.75, 950.43 and 405.28

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Solution

The fourth proportional to 688.75, 950.43 and 405.28 is: 559.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    688.75 : 950.43 = 405.28 : x
  2. Step 2: Convert to fraction form
    688.75/950.43 = 405.28/x
  3. Step 3: Cross multiply
    688.75x = 950.43 × 405.28
  4. Step 4: Simplify right side
    688.75x = 385,190.31
  5. Step 5: Solve for x
    x = 385,190.31/688.75
  6. Step 6: Final answer
    x = 559.26

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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.