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Finding the Fourth Proportional to 648.68, 972.98 and 215.78

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Solution

The fourth proportional to 648.68, 972.98 and 215.78 is: 323.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.68 : 972.98 = 215.78 : x
  2. Step 2: Convert to fraction form
    648.68/972.98 = 215.78/x
  3. Step 3: Cross multiply
    648.68x = 972.98 × 215.78
  4. Step 4: Simplify right side
    648.68x = 209,949.62
  5. Step 5: Solve for x
    x = 209,949.62/648.68
  6. Step 6: Final answer
    x = 323.66

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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.