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Finding the Fourth Proportional to 840.80, 1,261.20 and 263.66

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Solution

The fourth proportional to 840.80, 1,261.20 and 263.66 is: 395.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.80 : 1,261.20 = 263.66 : x
  2. Step 2: Convert to fraction form
    840.80/1,261.20 = 263.66/x
  3. Step 3: Cross multiply
    840.80x = 1,261.20 × 263.66
  4. Step 4: Simplify right side
    840.80x = 332,527.99
  5. Step 5: Solve for x
    x = 332,527.99/840.80
  6. Step 6: Final answer
    x = 395.49

Related Problems

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Double scale
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Similar ratio
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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.