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Finding the Fourth Proportional to 979.29, 1,351.80 and 630

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Solution

The fourth proportional to 979.29, 1,351.80 and 630 is: 869.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    979.29 : 1,351.80 = 630 : x
  2. Step 2: Convert to fraction form
    979.29/1,351.80 = 630/x
  3. Step 3: Cross multiply
    979.29x = 1,351.80 × 630
  4. Step 4: Simplify right side
    979.29x = 851,634
  5. Step 5: Solve for x
    x = 851,634/979.29
  6. Step 6: Final answer
    x = 869.64

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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.