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Finding the Fourth Proportional to 648.49, 972.81 and 215.65

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Solution

The fourth proportional to 648.49, 972.81 and 215.65 is: 323.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.49 : 972.81 = 215.65 : x
  2. Step 2: Convert to fraction form
    648.49/972.81 = 215.65/x
  3. Step 3: Cross multiply
    648.49x = 972.81 × 215.65
  4. Step 4: Simplify right side
    648.49x = 209,786.48
  5. Step 5: Solve for x
    x = 209,786.48/648.49
  6. Step 6: Final answer
    x = 323.50

Related Problems

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Half scale
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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.