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Finding the Fourth Proportional to 641.28, 885.78 and 494.76

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Solution

The fourth proportional to 641.28, 885.78 and 494.76 is: 683.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.28 : 885.78 = 494.76 : x
  2. Step 2: Convert to fraction form
    641.28/885.78 = 494.76/x
  3. Step 3: Cross multiply
    641.28x = 885.78 × 494.76
  4. Step 4: Simplify right side
    641.28x = 438,248.51
  5. Step 5: Solve for x
    x = 438,248.51/641.28
  6. Step 6: Final answer
    x = 683.40

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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.