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Finding the Fourth Proportional to 861.85, 1,293.06 and 393.49

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Solution

The fourth proportional to 861.85, 1,293.06 and 393.49 is: 590.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    861.85 : 1,293.06 = 393.49 : x
  2. Step 2: Convert to fraction form
    861.85/1,293.06 = 393.49/x
  3. Step 3: Cross multiply
    861.85x = 1,293.06 × 393.49
  4. Step 4: Simplify right side
    861.85x = 508,806.18
  5. Step 5: Solve for x
    x = 508,806.18/861.85
  6. Step 6: Final answer
    x = 590.37

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.