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Finding the Fourth Proportional to 628.69, 867.63 and 380.09

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Solution

The fourth proportional to 628.69, 867.63 and 380.09 is: 524.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.69 : 867.63 = 380.09 : x
  2. Step 2: Convert to fraction form
    628.69/867.63 = 380.09/x
  3. Step 3: Cross multiply
    628.69x = 867.63 × 380.09
  4. Step 4: Simplify right side
    628.69x = 329,777.49
  5. Step 5: Solve for x
    x = 329,777.49/628.69
  6. Step 6: Final answer
    x = 524.55

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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.