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Finding the Fourth Proportional to 782.69, 1,080.29 and 487.90

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Solution

The fourth proportional to 782.69, 1,080.29 and 487.90 is: 673.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.69 : 1,080.29 = 487.90 : x
  2. Step 2: Convert to fraction form
    782.69/1,080.29 = 487.90/x
  3. Step 3: Cross multiply
    782.69x = 1,080.29 × 487.90
  4. Step 4: Simplify right side
    782.69x = 527,070.28
  5. Step 5: Solve for x
    x = 527,070.28/782.69
  6. Step 6: Final answer
    x = 673.41

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1.5x scale

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.