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Finding the Fourth Proportional to 681.32, 940.20 and 485.66

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Solution

The fourth proportional to 681.32, 940.20 and 485.66 is: 670.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.32 : 940.20 = 485.66 : x
  2. Step 2: Convert to fraction form
    681.32/940.20 = 485.66/x
  3. Step 3: Cross multiply
    681.32x = 940.20 × 485.66
  4. Step 4: Simplify right side
    681.32x = 456,617.53
  5. Step 5: Solve for x
    x = 456,617.53/681.32
  6. Step 6: Final answer
    x = 670.20

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Half scale
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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.