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Finding the Fourth Proportional to 782.49, 1,080 and 487.56

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Solution

The fourth proportional to 782.49, 1,080 and 487.56 is: 672.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.49 : 1,080 = 487.56 : x
  2. Step 2: Convert to fraction form
    782.49/1,080 = 487.56/x
  3. Step 3: Cross multiply
    782.49x = 1,080 × 487.56
  4. Step 4: Simplify right side
    782.49x = 526,564.80
  5. Step 5: Solve for x
    x = 526,564.80/782.49
  6. Step 6: Final answer
    x = 672.93

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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.