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Finding the Fourth Proportional to 1,238.80, 1,710.18 and 819.76

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Solution

The fourth proportional to 1,238.80, 1,710.18 and 819.76 is: 1,131.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,238.80 : 1,710.18 = 819.76 : x
  2. Step 2: Convert to fraction form
    1,238.80/1,710.18 = 819.76/x
  3. Step 3: Cross multiply
    1,238.80x = 1,710.18 × 819.76
  4. Step 4: Simplify right side
    1,238.80x = 1,401,937.16
  5. Step 5: Solve for x
    x = 1,401,937.16/1,238.80
  6. Step 6: Final answer
    x = 1,131.69

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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.