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Finding the Fourth Proportional to 804.86, 1,108.23 and 638.54

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Solution

The fourth proportional to 804.86, 1,108.23 and 638.54 is: 879.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.86 : 1,108.23 = 638.54 : x
  2. Step 2: Convert to fraction form
    804.86/1,108.23 = 638.54/x
  3. Step 3: Cross multiply
    804.86x = 1,108.23 × 638.54
  4. Step 4: Simplify right side
    804.86x = 707,649.18
  5. Step 5: Solve for x
    x = 707,649.18/804.86
  6. Step 6: Final answer
    x = 879.22

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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.