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Finding the Fourth Proportional to 869.38, 1,200.12 and 520

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Solution

The fourth proportional to 869.38, 1,200.12 and 520 is: 717.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.38 : 1,200.12 = 520 : x
  2. Step 2: Convert to fraction form
    869.38/1,200.12 = 520/x
  3. Step 3: Cross multiply
    869.38x = 1,200.12 × 520
  4. Step 4: Simplify right side
    869.38x = 624,062.40
  5. Step 5: Solve for x
    x = 624,062.40/869.38
  6. Step 6: Final answer
    x = 717.82

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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.