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Finding the Fourth Proportional to 828.32, 1,143.76 and 641.49

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Solution

The fourth proportional to 828.32, 1,143.76 and 641.49 is: 885.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.32 : 1,143.76 = 641.49 : x
  2. Step 2: Convert to fraction form
    828.32/1,143.76 = 641.49/x
  3. Step 3: Cross multiply
    828.32x = 1,143.76 × 641.49
  4. Step 4: Simplify right side
    828.32x = 733,710.60
  5. Step 5: Solve for x
    x = 733,710.60/828.32
  6. Step 6: Final answer
    x = 885.78

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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.