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Finding the Fourth Proportional to 643.55, 888.16 and 538.45

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Solution

The fourth proportional to 643.55, 888.16 and 538.45 is: 743.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.55 : 888.16 = 538.45 : x
  2. Step 2: Convert to fraction form
    643.55/888.16 = 538.45/x
  3. Step 3: Cross multiply
    643.55x = 888.16 × 538.45
  4. Step 4: Simplify right side
    643.55x = 478,229.28
  5. Step 5: Solve for x
    x = 478,229.28/643.55
  6. Step 6: Final answer
    x = 743.11

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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.