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Finding the Fourth Proportional to 806.80, 1,112.76 and 620

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Solution

The fourth proportional to 806.80, 1,112.76 and 620 is: 855.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.80 : 1,112.76 = 620 : x
  2. Step 2: Convert to fraction form
    806.80/1,112.76 = 620/x
  3. Step 3: Cross multiply
    806.80x = 1,112.76 × 620
  4. Step 4: Simplify right side
    806.80x = 689,911.20
  5. Step 5: Solve for x
    x = 689,911.20/806.80
  6. Step 6: Final answer
    x = 855.12

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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.