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Finding the Fourth Proportional to 628.82, 867.82 and 380.15

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Solution

The fourth proportional to 628.82, 867.82 and 380.15 is: 524.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.82 : 867.82 = 380.15 : x
  2. Step 2: Convert to fraction form
    628.82/867.82 = 380.15/x
  3. Step 3: Cross multiply
    628.82x = 867.82 × 380.15
  4. Step 4: Simplify right side
    628.82x = 329,905.33
  5. Step 5: Solve for x
    x = 329,905.33/628.82
  6. Step 6: Final answer
    x = 524.64

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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.