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Finding the Fourth Proportional to 891.09, 1,229.70 and 492.75

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Solution

The fourth proportional to 891.09, 1,229.70 and 492.75 is: 679.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.09 : 1,229.70 = 492.75 : x
  2. Step 2: Convert to fraction form
    891.09/1,229.70 = 492.75/x
  3. Step 3: Cross multiply
    891.09x = 1,229.70 × 492.75
  4. Step 4: Simplify right side
    891.09x = 605,934.68
  5. Step 5: Solve for x
    x = 605,934.68/891.09
  6. Step 6: Final answer
    x = 679.99

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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.