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Finding the Fourth Proportional to 712.80, 982.98 and 634.20

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Solution

The fourth proportional to 712.80, 982.98 and 634.20 is: 874.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    712.80 : 982.98 = 634.20 : x
  2. Step 2: Convert to fraction form
    712.80/982.98 = 634.20/x
  3. Step 3: Cross multiply
    712.80x = 982.98 × 634.20
  4. Step 4: Simplify right side
    712.80x = 623,405.92
  5. Step 5: Solve for x
    x = 623,405.92/712.80
  6. Step 6: Final answer
    x = 874.59

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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.