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Finding the Fourth Proportional to 643.10, 886.92 and 518.72

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Solution

The fourth proportional to 643.10, 886.92 and 518.72 is: 715.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.10 : 886.92 = 518.72 : x
  2. Step 2: Convert to fraction form
    643.10/886.92 = 518.72/x
  3. Step 3: Cross multiply
    643.10x = 886.92 × 518.72
  4. Step 4: Simplify right side
    643.10x = 460,063.14
  5. Step 5: Solve for x
    x = 460,063.14/643.10
  6. Step 6: Final answer
    x = 715.38

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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.