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Finding the Fourth Proportional to 891.30, 1,229.97 and 498.30

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Solution

The fourth proportional to 891.30, 1,229.97 and 498.30 is: 687.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    891.30 : 1,229.97 = 498.30 : x
  2. Step 2: Convert to fraction form
    891.30/1,229.97 = 498.30/x
  3. Step 3: Cross multiply
    891.30x = 1,229.97 × 498.30
  4. Step 4: Simplify right side
    891.30x = 612,894.05
  5. Step 5: Solve for x
    x = 612,894.05/891.30
  6. Step 6: Final answer
    x = 687.64

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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.