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Finding the Fourth Proportional to 643.95, 888.26 and 395.18

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Solution

The fourth proportional to 643.95, 888.26 and 395.18 is: 545.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.95 : 888.26 = 395.18 : x
  2. Step 2: Convert to fraction form
    643.95/888.26 = 395.18/x
  3. Step 3: Cross multiply
    643.95x = 888.26 × 395.18
  4. Step 4: Simplify right side
    643.95x = 351,016.17
  5. Step 5: Solve for x
    x = 351,016.17/643.95
  6. Step 6: Final answer
    x = 545.10

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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.