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Finding the Fourth Proportional to 890.48, 1,228.31 and 641.34

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Solution

The fourth proportional to 890.48, 1,228.31 and 641.34 is: 884.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.48 : 1,228.31 = 641.34 : x
  2. Step 2: Convert to fraction form
    890.48/1,228.31 = 641.34/x
  3. Step 3: Cross multiply
    890.48x = 1,228.31 × 641.34
  4. Step 4: Simplify right side
    890.48x = 787,761.13
  5. Step 5: Solve for x
    x = 787,761.13/890.48
  6. Step 6: Final answer
    x = 884.65

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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.