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Finding the Fourth Proportional to 643.79, 888.51 and 395.06

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Solution

The fourth proportional to 643.79, 888.51 and 395.06 is: 545.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.79 : 888.51 = 395.06 : x
  2. Step 2: Convert to fraction form
    643.79/888.51 = 395.06/x
  3. Step 3: Cross multiply
    643.79x = 888.51 × 395.06
  4. Step 4: Simplify right side
    643.79x = 351,014.76
  5. Step 5: Solve for x
    x = 351,014.76/643.79
  6. Step 6: Final answer
    x = 545.24

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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.