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Finding the Fourth Proportional to 860.40, 1,285.40 and 549.62

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Solution

The fourth proportional to 860.40, 1,285.40 and 549.62 is: 821.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    860.40 : 1,285.40 = 549.62 : x
  2. Step 2: Convert to fraction form
    860.40/1,285.40 = 549.62/x
  3. Step 3: Cross multiply
    860.40x = 1,285.40 × 549.62
  4. Step 4: Simplify right side
    860.40x = 706,481.55
  5. Step 5: Solve for x
    x = 706,481.55/860.40
  6. Step 6: Final answer
    x = 821.11

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.