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Finding the Fourth Proportional to 628.45, 942.80 and 217.64

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Solution

The fourth proportional to 628.45, 942.80 and 217.64 is: 326.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.45 : 942.80 = 217.64 : x
  2. Step 2: Convert to fraction form
    628.45/942.80 = 217.64/x
  3. Step 3: Cross multiply
    628.45x = 942.80 × 217.64
  4. Step 4: Simplify right side
    628.45x = 205,190.99
  5. Step 5: Solve for x
    x = 205,190.99/628.45
  6. Step 6: Final answer
    x = 326.50

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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.