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Finding the Fourth Proportional to 820.99, 1,133.89 and 636.71

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Solution

The fourth proportional to 820.99, 1,133.89 and 636.71 is: 879.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.99 : 1,133.89 = 636.71 : x
  2. Step 2: Convert to fraction form
    820.99/1,133.89 = 636.71/x
  3. Step 3: Cross multiply
    820.99x = 1,133.89 × 636.71
  4. Step 4: Simplify right side
    820.99x = 721,959.10
  5. Step 5: Solve for x
    x = 721,959.10/820.99
  6. Step 6: Final answer
    x = 879.38

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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.