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Finding the Fourth Proportional to 869.91, 1,304.90 and 641.49

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Solution

The fourth proportional to 869.91, 1,304.90 and 641.49 is: 962.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.91 : 1,304.90 = 641.49 : x
  2. Step 2: Convert to fraction form
    869.91/1,304.90 = 641.49/x
  3. Step 3: Cross multiply
    869.91x = 1,304.90 × 641.49
  4. Step 4: Simplify right side
    869.91x = 837,080.30
  5. Step 5: Solve for x
    x = 837,080.30/869.91
  6. Step 6: Final answer
    x = 962.26

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.