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Finding the Fourth Proportional to 628.80, 868.02 and 380.34

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Solution

The fourth proportional to 628.80, 868.02 and 380.34 is: 525.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 868.02 = 380.34 : x
  2. Step 2: Convert to fraction form
    628.80/868.02 = 380.34/x
  3. Step 3: Cross multiply
    628.80x = 868.02 × 380.34
  4. Step 4: Simplify right side
    628.80x = 330,142.73
  5. Step 5: Solve for x
    x = 330,142.73/628.80
  6. Step 6: Final answer
    x = 525.04

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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.