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Finding the Fourth Proportional to 782.40, 1,079.71 and 450.89

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Solution

The fourth proportional to 782.40, 1,079.71 and 450.89 is: 622.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.40 : 1,079.71 = 450.89 : x
  2. Step 2: Convert to fraction form
    782.40/1,079.71 = 450.89/x
  3. Step 3: Cross multiply
    782.40x = 1,079.71 × 450.89
  4. Step 4: Simplify right side
    782.40x = 486,830.44
  5. Step 5: Solve for x
    x = 486,830.44/782.40
  6. Step 6: Final answer
    x = 622.23

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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.