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Finding the Fourth Proportional to 905.89, 1,250.10 and 491.89

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Solution

The fourth proportional to 905.89, 1,250.10 and 491.89 is: 678.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    905.89 : 1,250.10 = 491.89 : x
  2. Step 2: Convert to fraction form
    905.89/1,250.10 = 491.89/x
  3. Step 3: Cross multiply
    905.89x = 1,250.10 × 491.89
  4. Step 4: Simplify right side
    905.89x = 614,911.69
  5. Step 5: Solve for x
    x = 614,911.69/905.89
  6. Step 6: Final answer
    x = 678.79

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Double scale
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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.