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Finding the Fourth Proportional to 656.90, 985.50 and 218.12

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Solution

The fourth proportional to 656.90, 985.50 and 218.12 is: 327.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.90 : 985.50 = 218.12 : x
  2. Step 2: Convert to fraction form
    656.90/985.50 = 218.12/x
  3. Step 3: Cross multiply
    656.90x = 985.50 × 218.12
  4. Step 4: Simplify right side
    656.90x = 214,951.41
  5. Step 5: Solve for x
    x = 214,951.41/656.90
  6. Step 6: Final answer
    x = 327.22

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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.