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Finding the Fourth Proportional to 631.70, 872.30 and 611.05

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Solution

The fourth proportional to 631.70, 872.30 and 611.05 is: 843.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.70 : 872.30 = 611.05 : x
  2. Step 2: Convert to fraction form
    631.70/872.30 = 611.05/x
  3. Step 3: Cross multiply
    631.70x = 872.30 × 611.05
  4. Step 4: Simplify right side
    631.70x = 533,018.92
  5. Step 5: Solve for x
    x = 533,018.92/631.70
  6. Step 6: Final answer
    x = 843.78

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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.