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Finding the Fourth Proportional to 782.80, 1,079.97 and 487.81

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Solution

The fourth proportional to 782.80, 1,079.97 and 487.81 is: 672.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.80 : 1,079.97 = 487.81 : x
  2. Step 2: Convert to fraction form
    782.80/1,079.97 = 487.81/x
  3. Step 3: Cross multiply
    782.80x = 1,079.97 × 487.81
  4. Step 4: Simplify right side
    782.80x = 526,820.17
  5. Step 5: Solve for x
    x = 526,820.17/782.80
  6. Step 6: Final answer
    x = 672.99

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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.