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Finding the Fourth Proportional to 805.39, 1,111.51 and 490.58

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Solution

The fourth proportional to 805.39, 1,111.51 and 490.58 is: 677.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.39 : 1,111.51 = 490.58 : x
  2. Step 2: Convert to fraction form
    805.39/1,111.51 = 490.58/x
  3. Step 3: Cross multiply
    805.39x = 1,111.51 × 490.58
  4. Step 4: Simplify right side
    805.39x = 545,288.31
  5. Step 5: Solve for x
    x = 545,288.31/805.39
  6. Step 6: Final answer
    x = 677.05

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Double scale
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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.