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Finding the Fourth Proportional to 643.59, 886.38 and 555.05

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Solution

The fourth proportional to 643.59, 886.38 and 555.05 is: 764.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.59 : 886.38 = 555.05 : x
  2. Step 2: Convert to fraction form
    643.59/886.38 = 555.05/x
  3. Step 3: Cross multiply
    643.59x = 886.38 × 555.05
  4. Step 4: Simplify right side
    643.59x = 491,980.79
  5. Step 5: Solve for x
    x = 491,980.79/643.59
  6. Step 6: Final answer
    x = 764.43

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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.