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Finding the Fourth Proportional to 628.80, 868.02 and 380.16

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Solution

The fourth proportional to 628.80, 868.02 and 380.16 is: 524.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.80 : 868.02 = 380.16 : x
  2. Step 2: Convert to fraction form
    628.80/868.02 = 380.16/x
  3. Step 3: Cross multiply
    628.80x = 868.02 × 380.16
  4. Step 4: Simplify right side
    628.80x = 329,986.48
  5. Step 5: Solve for x
    x = 329,986.48/628.80
  6. Step 6: Final answer
    x = 524.79

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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.