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Finding the Fourth Proportional to 782.30, 1,079.59 and 428.22

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Solution

The fourth proportional to 782.30, 1,079.59 and 428.22 is: 590.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.30 : 1,079.59 = 428.22 : x
  2. Step 2: Convert to fraction form
    782.30/1,079.59 = 428.22/x
  3. Step 3: Cross multiply
    782.30x = 1,079.59 × 428.22
  4. Step 4: Simplify right side
    782.30x = 462,302.03
  5. Step 5: Solve for x
    x = 462,302.03/782.30
  6. Step 6: Final answer
    x = 590.95

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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.